631668 has 12 divisors (see below), whose sum is σ = 1473920. Its totient is φ = 210552.

The previous prime is 631667. The next prime is 631679. The reversal of 631668 is 866136.

631668 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (12).

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (631667) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26308 + ... + 26331.

2⁶³¹⁶⁶⁸ is an apocalyptic number.

It is an amenable number.

631668 is an abundant number, since it is smaller than the sum of its proper divisors (842252).

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

631668 is a wasteful number, since it uses less digits than its factorization.

631668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52646 (or 52644 counting only the distinct ones).

The product of its digits is 5184, while the sum is 30.

The square root of 631668 is about 794.7754399829. The cubic root of 631668 is about 85.8017789145.

The spelling of 631668 in words is "six hundred thirty-one thousand, six hundred sixty-eight".