646639886016 has 448 divisors, whose sum is σ = 1998805248000. Its totient is φ = 204732702720.

The previous prime is 646639886003. The next prime is 646639886023. The reversal of 646639886016 is 610688936646.

646639886016 is a `hidden beast` number, since 6 + 466 + 3 + 98 + 86 + 0 + 1 + 6 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 899359705 + ... + 899360423.

Almost surely, 2^646639886016 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 646639886016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (999402624000).

646639886016 is an abundant number, since it is smaller than the sum of its proper divisors (1352165361984).

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

646639886016 is a wasteful number, since it uses less digits than its factorization.

646639886016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1037 (or 1021 counting only the distinct ones).

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

The spelling of 646639886016 in words is "six hundred forty-six billion, six hundred thirty-nine million, eight hundred eighty-six thousand, sixteen".