Cordial saludo.
Coloca el siguiente macro en un módulo del editor de Visual Basic. Cuando lo hayas copiado, vas a tu hoja y colocas en una celda cualquiera un numero(Por Ej. en B4) y en otra celda colocas esta instrucción: =numletras(B4;1). Así obtendras lo que quieres.
Tienes que tener habilitada la opcion de ejecución de macros.
Exitos
Option Explicit
Dim cTexto As String 'Variable para las funciones
Public Function NumLetras(ByVal Numero As Double, ByVal Mayusculas As Integer) As String
Dim NumTmp As String
Dim c01 As Integer
Dim c02 As Integer
Dim pos As Integer
Dim dig As Integer
Dim cen As Integer
Dim dec As Integer
Dim uni As Integer
Dim letra1 As String
Dim letra2 As String
Dim letra3 As String
Dim Leyenda As String
Dim Leyenda1 As String
Dim TFNumero As String
If Numero < 0 Then Numero = Abs(Numero)
NumTmp = Format(Numero, "000000000000000.00") 'Le da un formato fijo
c01 = 1
pos = 1
TFNumero = ""
'Para extraer tres digitos cada vez
Do While c01 <= 5
c02 = 1
Do While c02 <= 3
'Extrae un digito cada vez de izquierda a derecha
dig = Val(Mid(NumTmp, pos, 1))
Select Case c02
Case 1: cen = dig
Case 2: dec = dig
Case 3: uni = dig
End Select
c02 = c02 + 1
pos = pos + 1
Loop
letra3 = Centena(uni, dec, cen)
letra2 = Decena(uni, dec)
letra1 = Unidad(uni, dec)
Select Case c01
Case 1
If cen + dec + uni = 1 Then
Leyenda = "Billon "
ElseIf cen + dec + uni > 1 Then
Leyenda = "Billones "
End If
Case 2
If cen + dec + uni >= 1 And Val(Mid(NumTmp, 7, 3)) = 0 Then
Leyenda = "Mil Millones "
ElseIf cen + dec + uni >= 1 Then
Leyenda = "Mil "
End If
Case 3
If cen + dec = 0 And uni = 1 Then
Leyenda = "Millon "
ElseIf cen > 0 Or dec > 0 Or uni > 1 Then
Leyenda = "Millones "
End If
Case 4
If cen + dec + uni >= 1 Then
Leyenda = "Mil "
End If
Case 5
If cen + dec + uni >= 1 Then
Leyenda = ""
End If
End Select
c01 = c01 + 1
TFNumero = TFNumero + letra3 + letra2 + letra1 + Leyenda
Leyenda = ""
letra1 = ""
letra2 = ""
letra3 = ""
Loop
If Val(NumTmp) = 0 Or Val(NumTmp) < 1 Then
Leyenda1 = "Cero Pesos "
ElseIf Val(NumTmp) = 1 Or Val(NumTmp) < 2 Then
Leyenda1 = "Peso "
ElseIf Val(Mid(NumTmp, 4, 12)) = 0 Or Val(Mid(NumTmp, 10, 6)) = 0 Then
Leyenda1 = "de Pesos "
Else
Leyenda1 = "Pesos "
End If
TFNumero = "(" & TFNumero & Leyenda1 & Mid(NumTmp, 17) & "/100 M.N.)"
If Mayusculas = 1 Then
TFNumero = UCase(TFNumero)
Else
TFNumero = LCase(TFNumero)
End If
NumLetras = TFNumero
End Function
Private Function Centena(ByVal uni As Integer, ByVal dec As Integer, _
ByVal cen As Integer) As String
Select Case cen
Case 1
If dec + uni = 0 Then
cTexto = "cien "
Else
cTexto = "ciento "
End If
Case 2: cTexto = "doscientos "
Case 3: cTexto = "trescientos "
Case 4: cTexto = "cuatrocientos "
Case 5: cTexto = "quinientos "
Case 6: cTexto = "seiscientos "
Case 7: cTexto = "setecientos "
Case 8: cTexto = "ochocientos "
Case 9: cTexto = "novecientos "
Case Else: cTexto = ""
End Select
Centena = cTexto
cTexto = ""
End Function
Private Function Decena(ByVal uni As Integer, ByVal dec As Integer) As String
Select Case dec
Case 1
Select Case uni
Case 0: cTexto = "diez "
Case 1: cTexto = "once "
Case 2: cTexto = "doce "
Case 3: cTexto = "trece "
Case 4: cTexto = "catorce "
Case 5: cTexto = "quince "
Case 6 To 9: cTexto = "dieci"
End Select
Case 2
If uni = 0 Then
cTexto = "veinte "
ElseIf uni > 0 Then
cTexto = "veinti"
End If
Case 3: cTexto = "treinta "
Case 4: cTexto = "cuarenta "
Case 5: cTexto = "cincuenta "
Case 6: cTexto = "sesenta "
Case 7: cTexto = "setenta "
Case 8: cTexto = "ochenta "
Case 9: cTexto = "noventa "
Case Else: cTexto = ""
End Select
If uni > 0 And dec > 2 Then cTexto = cTexto + "y "
Decena = cTexto
cTexto = ""
End Function
Private Function Unidad(ByVal uni As Integer, ByVal dec As Integer) As String
If dec <> 1 Then
Select Case uni
Case 1: cTexto = "un "
Case 2: cTexto = "dos "
Case 3: cTexto = "tres "
Case 4: cTexto = "cuatro "
Case 5: cTexto = "cinco "
End Select
End If
Select Case uni
Case 6: cTexto = "seis "
Case 7: cTexto = "siete "
Case 8: cTexto = "ocho "
Case 9: cTexto = "nueve "
End Select
Unidad = cTexto
cTexto = ""
End Function
Exitos
Diego