31917784009905 has 128 divisors (see below), whose sum is σ = 60527919513600. Its totient is φ = 15902231288832.

The previous prime is 31917784009897. The next prime is 31917784009921. The reversal of 31917784009905 is 50990048771913.

It is not a de Polignac number, because 31917784009905 - 2³ = 31917784009897 is a prime.

It is a super-2 number, since 2×31917784009905² (a number of 28 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1590867904 + ... + 1590887966.

It is an arithmetic number, because the mean of its divisors is an integer number (472874371200).

Almost surely, 2^{31917784009905} is an apocalyptic number.

It is an amenable number.

31917784009905 is a deficient number, since it is larger than the sum of its proper divisors (28610135503695).

31917784009905 is a wasteful number, since it uses less digits than its factorization.

31917784009905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25220 (or 25214 counting only the distinct ones).

The product of its (nonzero) digits is 17146080, while the sum is 63.

The spelling of 31917784009905 in words is "thirty-one trillion, nine hundred seventeen billion, seven hundred eighty-four million, nine thousand, nine hundred five".