81992304 has 40 divisors (see below), whose sum is σ = 235349520. Its totient is φ = 27330624.

The previous prime is 81992293. The next prime is 81992311. The reversal of 81992304 is 40329918.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 94467 + ... + 95330.

It is an arithmetic number, because the mean of its divisors is an integer number (5883738).

Almost surely, 2^81992304 is an apocalyptic number.

It is an amenable number.

81992304 is an abundant number, since it is smaller than the sum of its proper divisors (153357216).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81992304 is a wasteful number, since it uses less digits than its factorization.

81992304 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189814 (or 189802 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 81992304 is about 9054.9601876541. The cubic root of 81992304 is about 434.4345566356.

The spelling of 81992304 in words is "eighty-one million, nine hundred ninety-two thousand, three hundred four".