31631437861 has 16 divisors (see below), whose sum is σ = 34798256640. Its totient is φ = 28618896240.

The previous prime is 31631437847. The next prime is 31631437913. The reversal of 31631437861 is 16873413613.

It is a cyclic number.

It is not a de Polignac number, because 31631437861 - 2⁵ = 31631437829 is a prime.

It is a super-2 number, since 2×31631437861² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31631437841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 224706 + ... + 337276.

It is an arithmetic number, because the mean of its divisors is an integer number (2174891040).

Almost surely, 2^31631437861 is an apocalyptic number.

It is an amenable number.

31631437861 is a deficient number, since it is larger than the sum of its proper divisors (3166818779).

31631437861 is a wasteful number, since it uses less digits than its factorization.

31631437861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113256.

The product of its digits is 217728, while the sum is 43.

The spelling of 31631437861 in words is "thirty-one billion, six hundred thirty-one million, four hundred thirty-seven thousand, eight hundred sixty-one".