631668473856 has 396 divisors, whose sum is σ = 2125857309732. Its totient is φ = 180212465664.

The previous prime is 631668473827. The next prime is 631668473881. The reversal of 631668473856 is 658374866136.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a junction number, because it is equal to n+sod(n) for n = 631668473793 and 631668473802.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 924843691 + ... + 924844373.

Almost surely, 2^631668473856 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 631668473856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1062928654866).

631668473856 is an abundant number, since it is smaller than the sum of its proper divisors (1494188835876).

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

631668473856 is an frugal number, since it uses more digits than its factorization.

631668473856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 745 (or 695 counting only the distinct ones).

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

The spelling of 631668473856 in words is "six hundred thirty-one billion, six hundred sixty-eight million, four hundred seventy-three thousand, eight hundred fifty-six".