631786438656 has 640 divisors, whose sum is σ = 2063595600000. Its totient is φ = 192631799808.

The previous prime is 631786438529. The next prime is 631786438663. The reversal of 631786438656 is 656834687136.

631786438656 is a `hidden beast` number, since 63 + 1 + 7 + 86 + 438 + 65 + 6 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 631786438593 and 631786438602.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 21785739250 + ... + 21785739278.

It is an arithmetic number, because the mean of its divisors is an integer number (3224368125).

Almost surely, 2^631786438656 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 631786438656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1031797800000).

631786438656 is an abundant number, since it is smaller than the sum of its proper divisors (1431809161344).

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

631786438656 is an frugal number, since it uses more digits than its factorization.

631786438656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107 (or 53 counting only the distinct ones).

The product of its digits is 104509440, while the sum is 63.

The spelling of 631786438656 in words is "six hundred thirty-one billion, seven hundred eighty-six million, four hundred thirty-eight thousand, six hundred fifty-six".