80646561 has 6 divisors (see below), whose sum is σ = 116489490. Its totient is φ = 53764368.

The previous prime is 80646539. The next prime is 80646563. The reversal of 80646561 is 16564608.

80646561 is a `hidden beast` number, since 8 + 0 + 646 + 5 + 6 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 63680400 + 16966161 = 7980^2 + 4119^2 .

It is not a de Polignac number, because 80646561 - 2⁶ = 80646497 is a prime.

It is a super-2 number, since 2×80646561² = 13007735602253442, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (80646563) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4480356 + ... + 4480373.

It is an arithmetic number, because the mean of its divisors is an integer number (19414915).

Almost surely, 2^80646561 is an apocalyptic number.

It is an amenable number.

80646561 is a deficient number, since it is larger than the sum of its proper divisors (35842929).

80646561 is a wasteful number, since it uses less digits than its factorization.

80646561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8960735 (or 8960732 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 80646561 is about 8980.3430335372. The cubic root of 80646561 is about 432.0446359486.

The spelling of 80646561 in words is "eighty million, six hundred forty-six thousand, five hundred sixty-one".