81712492 has 12 divisors (see below), whose sum is σ = 143095680. Its totient is φ = 40828016.

The previous prime is 81712487. The next prime is 81712531. The reversal of 81712492 is 29421718.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 309 + ... + 12787.

It is an arithmetic number, because the mean of its divisors is an integer number (11924640).

Almost surely, 2^81712492 is an apocalyptic number.

It is an amenable number.

81712492 is a deficient number, since it is larger than the sum of its proper divisors (61383188).

81712492 is a wasteful number, since it uses less digits than its factorization.

81712492 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14120 (or 14118 counting only the distinct ones).

The product of its digits is 8064, while the sum is 34.

The square root of 81712492 is about 9039.4962249010. The cubic root of 81712492 is about 433.9398006644.

It can be divided in two parts, 817124 and 92, that added together give a square (817216 = 904²).

The spelling of 81712492 in words is "eighty-one million, seven hundred twelve thousand, four hundred ninety-two".