631386021 has 48 divisors (see below), whose sum is σ = 1016332800. Its totient is φ = 347276160.

The previous prime is 631385987. The next prime is 631386023. The reversal of 631386021 is 120683136.

631386021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 631386021 - 2⁹ = 631385509 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 631386021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (631386023) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1590195 + ... + 1590591.

It is an arithmetic number, because the mean of its divisors is an integer number (21173600).

Almost surely, 2^631386021 is an apocalyptic number.

It is an amenable number.

631386021 is a deficient number, since it is larger than the sum of its proper divisors (384946779).

631386021 is a wasteful number, since it uses less digits than its factorization.

631386021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 794 (or 787 counting only the distinct ones).

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

The square root of 631386021 is about 25127.3958260700. The cubic root of 631386021 is about 857.8900960068.

The spelling of 631386021 in words is "six hundred thirty-one million, three hundred eighty-six thousand, twenty-one".