31630007721 has 72 divisors (see below), whose sum is σ = 48409151040. Its totient is φ = 18327209472.

The previous prime is 31630007683. The next prime is 31630007779. The reversal of 31630007721 is 12770003613.

It is not a de Polignac number, because 31630007721 - 2¹⁰ = 31630006697 is a prime.

It is a super-2 number, since 2×31630007721² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (31630007221) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 62141215 + ... + 62141723.

It is an arithmetic number, because the mean of its divisors is an integer number (672349320).

Almost surely, 2^31630007721 is an apocalyptic number.

It is an amenable number.

31630007721 is a deficient number, since it is larger than the sum of its proper divisors (16779143319).

31630007721 is a wasteful number, since it uses less digits than its factorization.

31630007721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 707 (or 621 counting only the distinct ones).

The product of its (nonzero) digits is 5292, while the sum is 30.

The spelling of 31630007721 in words is "thirty-one billion, six hundred thirty million, seven thousand, seven hundred twenty-one".