81364924 has 48 divisors (see below), whose sum is σ = 157314528. Its totient is φ = 36661248.

The previous prime is 81364919. The next prime is 81364939. The reversal of 81364924 is 42946318.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 183447 + ... + 183889.

It is an arithmetic number, because the mean of its divisors is an integer number (3277386).

Almost surely, 2^81364924 is an apocalyptic number.

It is an amenable number.

81364924 is a deficient number, since it is larger than the sum of its proper divisors (75949604).

81364924 is a wasteful number, since it uses less digits than its factorization.

81364924 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 574 (or 572 counting only the distinct ones).

The product of its digits is 41472, while the sum is 37.

The square root of 81364924 is about 9020.2507725672. The cubic root of 81364924 is about 433.3236650045.

The spelling of 81364924 in words is "eighty-one million, three hundred sixty-four thousand, nine hundred twenty-four".