64893906864 has 200 divisors, whose sum is σ = 189827307120. Its totient is φ = 21401667072.

The previous prime is 64893906851. The next prime is 64893906887. The reversal of 64893906864 is 46860939846.

64893906864 is a `hidden beast` number, since 6 + 489 + 3 + 90 + 6 + 8 + 64 = 666.

It is a super-2 number, since 2×64893906864² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 58515142 + ... + 58516250.

Almost surely, 2^64893906864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64893906864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94913653560).

64893906864 is an abundant number, since it is smaller than the sum of its proper divisors (124933400256).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

64893906864 is a wasteful number, since it uses less digits than its factorization.

64893906864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1569 (or 1554 counting only the distinct ones).

The product of its (nonzero) digits is 53747712, while the sum is 63.

The spelling of 64893906864 in words is "sixty-four billion, eight hundred ninety-three million, nine hundred six thousand, eight hundred sixty-four".