81608456 has 16 divisors (see below), whose sum is σ = 153330000. Its totient is φ = 40720464.

The previous prime is 81608447. The next prime is 81608459. The reversal of 81608456 is 65480618.

It is not an unprimeable number, because it can be changed into a prime (81608459) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6230 + ... + 14213.

It is an arithmetic number, because the mean of its divisors is an integer number (9583125).

Almost surely, 2^81608456 is an apocalyptic number.

It is an amenable number.

81608456 is a deficient number, since it is larger than the sum of its proper divisors (71721544).

81608456 is a wasteful number, since it uses less digits than its factorization.

81608456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20948 (or 20944 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 38.

The square root of 81608456 is about 9033.7398678510. The cubic root of 81608456 is about 433.7555590093.

The spelling of 81608456 in words is "eighty-one million, six hundred eight thousand, four hundred fifty-six".