81560690 has 32 divisors (see below), whose sum is σ = 152216064. Its totient is φ = 31432320.

The previous prime is 81560671. The next prime is 81560701. The reversal of 81560690 is 9606518.

It is a super-2 number, since 2×81560690² = 13304292306552200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 81560690.

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, 94742 + ... + 95598.

It is an arithmetic number, because the mean of its divisors is an integer number (4756752).

Almost surely, 2^81560690 is an apocalyptic number.

81560690 is a deficient number, since it is larger than the sum of its proper divisors (70655374).

81560690 is a wasteful number, since it uses less digits than its factorization.

81560690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1202.

The product of its (nonzero) digits is 12960, while the sum is 35.

The square root of 81560690 is about 9031.0957253259. The cubic root of 81560690 is about 433.6709157724.

The spelling of 81560690 in words is "eighty-one million, five hundred sixty thousand, six hundred ninety".