631563321 has 4 divisors (see below), whose sum is σ = 842084432. Its totient is φ = 421042212.

The previous prime is 631563307. The next prime is 631563329. The reversal of 631563321 is 123365136.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 631563321 - 2⁷ = 631563193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (631563329) 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, 105260551 + ... + 105260556.

It is an arithmetic number, because the mean of its divisors is an integer number (210521108).

Almost surely, 2^631563321 is an apocalyptic number.

It is an amenable number.

631563321 is a deficient number, since it is larger than the sum of its proper divisors (210521111).

631563321 is a wasteful number, since it uses less digits than its factorization.

631563321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210521110.

The product of its digits is 9720, while the sum is 30.

The square root of 631563321 is about 25130.9236002181. The cubic root of 631563321 is about 857.9703900867.

The spelling of 631563321 in words is "six hundred thirty-one million, five hundred sixty-three thousand, three hundred twenty-one".