31504681971 has 36 divisors (see below), whose sum is σ = 54005361072. Its totient is φ = 18002649168.

The previous prime is 31504681951. The next prime is 31504681973. The reversal of 31504681971 is 17918640513.

31504681971 is a `hidden beast` number, since 3 + 1 + 504 + 68 + 19 + 71 = 666.

It is not a de Polignac number, because 31504681971 - 2⁵ = 31504681939 is a prime.

It is not an unprimeable number, because it can be changed into a prime (31504681973) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 297060 + ... + 388913.

Almost surely, 2^31504681971 is an apocalyptic number.

31504681971 is a deficient number, since it is larger than the sum of its proper divisors (22500679101).

31504681971 is an frugal number, since it uses more digits than its factorization.

31504681971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 686004 (or 685983 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 45.

The spelling of 31504681971 in words is "thirty-one billion, five hundred four million, six hundred eighty-one thousand, nine hundred seventy-one".