• ← EvenQ
• → InexactNumberQ

ExactNumberQ

WMA link

ExactNumberQ[expr]

returns True if expr is an exact real or complex number, and returns
False otherwise.

• • ExactNumberQ[10]

ExactNumber[] of a Real or MachineReal is False

• • ExactNumberQ[10.0]

ExactNumberQ for complex numbers:

• • ExactNumberQ[I]

• • ExactNumberQ[1 + I]

but not when composed with a Real:

• • ExactNumberQ[1. + I]

ExactNumber[] is True for Rational numbers:

• • ExactNumberQ[5/6]

• • ExactNumberQ[4 * I + 5/6]