81575536 has 40 divisors (see below), whose sum is σ = 181238400. Its totient is φ = 34843584.

The previous prime is 81575519. The next prime is 81575561. The reversal of 81575536 is 63557518.

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, 37815 + ... + 39913.

It is an arithmetic number, because the mean of its divisors is an integer number (4530960).

Almost surely, 2^81575536 is an apocalyptic number.

It is an amenable number.

81575536 is an abundant number, since it is smaller than the sum of its proper divisors (99662864).

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

81575536 is a wasteful number, since it uses less digits than its factorization.

81575536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2461 (or 2455 counting only the distinct ones).

The product of its digits is 126000, while the sum is 40.

The square root of 81575536 is about 9031.9176258423. The cubic root of 81575536 is about 433.6972270089.

The spelling of 81575536 in words is "eighty-one million, five hundred seventy-five thousand, five hundred thirty-six".