646627656400 has 120 divisors (see below), whose sum is σ = 1696238005248. Its totient is φ = 234931200000.

The previous prime is 646627656379. The next prime is 646627656419. The reversal of 646627656400 is 4656726646.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5000560 + ... + 5128240.

Almost surely, 2^646627656400 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 646627656400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (848119002624).

646627656400 is an abundant number, since it is smaller than the sum of its proper divisors (1049610348848).

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

646627656400 is a wasteful number, since it uses less digits than its factorization.

646627656400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128861 (or 128850 counting only the distinct ones).

The product of its (nonzero) digits is 8709120, while the sum is 52.

The spelling of 646627656400 in words is "six hundred forty-six billion, six hundred twenty-seven million, six hundred fifty-six thousand, four hundred".