31517214509 has 24 divisors (see below), whose sum is σ = 36394323840. Its totient is φ = 27051096000.

The previous prime is 31517214503. The next prime is 31517214523. The reversal of 31517214509 is 90541271513.

It is a de Polignac number, because none of the positive numbers 2^k-31517214509 is a prime.

It is a super-2 number, since 2×31517214509² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31517214503) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 397052 + ... + 469770.

It is an arithmetic number, because the mean of its divisors is an integer number (1516430160).

Almost surely, 2^31517214509 is an apocalyptic number.

It is an amenable number.

31517214509 is a deficient number, since it is larger than the sum of its proper divisors (4877109331).

31517214509 is a wasteful number, since it uses less digits than its factorization.

31517214509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72833 (or 72802 counting only the distinct ones).

The product of its (nonzero) digits is 37800, while the sum is 38.

The spelling of 31517214509 in words is "thirty-one billion, five hundred seventeen million, two hundred fourteen thousand, five hundred nine".