81604552 has 32 divisors (see below), whose sum is σ = 162388800. Its totient is φ = 38361664.

The previous prime is 81604547. The next prime is 81604597. The reversal of 81604552 is 25540618.

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, 7098 + ... + 14614.

It is an arithmetic number, because the mean of its divisors is an integer number (5074650).

Almost surely, 2^81604552 is an apocalyptic number.

It is an amenable number.

81604552 is a deficient number, since it is larger than the sum of its proper divisors (80784248).

81604552 is a wasteful number, since it uses less digits than its factorization.

81604552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7605 (or 7601 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 31.

The square root of 81604552 is about 9033.5237864302. The cubic root of 81604552 is about 433.7486422069.

The spelling of 81604552 in words is "eighty-one million, six hundred four thousand, five hundred fifty-two".