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Mathematica Teacher's Edition

Built-in Functions

Mathematical Functions

Number Theory

IntegerExponent

IntegerExponent[n, b] gives the highest power of b that divides n.

IntegerExponent[n] is equivalent to IntegerExponent[n, 10].
IntegerExponent[n, b] gives the number of trailing zeros in the digits of n in base b.
See The Mathematica Book on the web: Section 3.1.3 and Section 3.2.4.
See also: IntegerDigits, FactorInteger, DigitCount, Exponent.

Further Examples