646622256 has 80 divisors (see below), whose sum is σ = 1912774400. Its totient is φ = 184391424.

The previous prime is 646622243. The next prime is 646622267. The reversal of 646622256 is 652226646.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 206430 + ... + 209538.

It is an arithmetic number, because the mean of its divisors is an integer number (23909680).

Almost surely, 2^646622256 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 646622256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (956387200).

646622256 is an abundant number, since it is smaller than the sum of its proper divisors (1266152144).

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

646622256 is a wasteful number, since it uses less digits than its factorization.

646622256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3746 (or 3740 counting only the distinct ones).

The product of its digits is 207360, while the sum is 39.

The square root of 646622256 is about 25428.7682753216. The cubic root of 646622256 is about 864.7360197732.

The spelling of 646622256 in words is "six hundred forty-six million, six hundred twenty-two thousand, two hundred fifty-six".