631253621 has 4 divisors (see below), whose sum is σ = 631849644. Its totient is φ = 630657600.

The previous prime is 631253611. The next prime is 631253641. The reversal of 631253621 is 126352136.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 540051121 + 91202500 = 23239^2 + 9550^2 .

It is a cyclic number.

It is not a de Polignac number, because 631253621 - 2¹⁸ = 630991477 is a prime.

It is a super-2 number, since 2×631253621² = 796962268051223282, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (631253611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 296420 + ... + 298541.

It is an arithmetic number, because the mean of its divisors is an integer number (157962411).

Almost surely, 2^631253621 is an apocalyptic number.

It is an amenable number.

631253621 is a deficient number, since it is larger than the sum of its proper divisors (596023).

631253621 is a wasteful number, since it uses less digits than its factorization.

631253621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 596022.

The product of its digits is 6480, while the sum is 29.

The square root of 631253621 is about 25124.7611132922. The cubic root of 631253621 is about 857.8301260437.

The spelling of 631253621 in words is "six hundred thirty-one million, two hundred fifty-three thousand, six hundred twenty-one".