64810881 has 16 divisors (see below), whose sum is σ = 101070400. Its totient is φ = 40932864.

The previous prime is 64810819. The next prime is 64810883. The reversal of 64810881 is 18801846.

64810881 is a `hidden beast` number, since 648 + 1 + 0 + 8 + 8 + 1 = 666.

It is not a de Polignac number, because 64810881 - 2¹¹ = 64808833 is a prime.

It is a super-2 number, since 2×64810881² = 8400900591992322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64810883) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 62656 + ... + 63681.

It is an arithmetic number, because the mean of its divisors is an integer number (6316900).

Almost surely, 2^64810881 is an apocalyptic number.

It is an amenable number.

64810881 is a deficient number, since it is larger than the sum of its proper divisors (36259519).

64810881 is a wasteful number, since it uses less digits than its factorization.

64810881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126365 (or 126359 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 36.

The square root of 64810881 is about 8050.5205421761. The cubic root of 64810881 is about 401.6822505810.

The spelling of 64810881 in words is "sixty-four million, eight hundred ten thousand, eight hundred eighty-one".