31516680 has 128 divisors (see below), whose sum is σ = 103420800. Its totient is φ = 7636992.

The previous prime is 31516669. The next prime is 31516697. The reversal of 31516680 is 8661513.

It is a super-2 number, since 2×31516680² = 1986602236444800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 138727 + ... + 138953.

It is an arithmetic number, because the mean of its divisors is an integer number (807975).

Almost surely, 2^31516680 is an apocalyptic number.

31516680 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31516680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (51710400).

31516680 is an abundant number, since it is smaller than the sum of its proper divisors (71904120).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31516680 is a wasteful number, since it uses less digits than its factorization.

31516680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 343 (or 339 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 31516680 is about 5613.9718560036. The cubic root of 31516680 is about 315.8737144263.

The spelling of 31516680 in words is "thirty-one million, five hundred sixteen thousand, six hundred eighty".