81920716 has 12 divisors (see below), whose sum is σ = 144275488. Its totient is φ = 40699152.

The previous prime is 81920711. The next prime is 81920717. The reversal of 81920716 is 61702918.

It is a happy number.

It is a super-2 number, since 2×81920716² = 13422007419905312, which contains 22 as substring.

It is a hoax number, since the sum of its digits (34) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (81920711) 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, 64596 + ... + 65851.

Almost surely, 2^81920716 is an apocalyptic number.

It is an amenable number.

81920716 is a deficient number, since it is larger than the sum of its proper divisors (62354772).

81920716 is a wasteful number, since it uses less digits than its factorization.

81920716 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130608 (or 130606 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 34.

The square root of 81920716 is about 9051.0063528870. The cubic root of 81920716 is about 434.3080839660.

The spelling of 81920716 in words is "eighty-one million, nine hundred twenty thousand, seven hundred sixteen".