31290560 has 112 divisors (see below), whose sum is σ = 86928960. Its totient is φ = 10506240.

The previous prime is 31290559. The next prime is 31290577. The reversal of 31290560 is 6509213.

It is a tau number, because it is divible by the number of its divisors (112).

It is a super-2 number, since 2×31290560² = 1958198290227200, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 136526 + ... + 136754.

Almost surely, 2^31290560 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31290560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43464480).

31290560 is an abundant number, since it is smaller than the sum of its proper divisors (55638400).

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

31290560 is a wasteful number, since it uses less digits than its factorization.

31290560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 314 (or 304 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 26.

The square root of 31290560 is about 5593.7965640520. The cubic root of 31290560 is about 315.1164766198.

Adding to 31290560 its reverse (6509213), we get a palindrome (37799773).

The spelling of 31290560 in words is "thirty-one million, two hundred ninety thousand, five hundred sixty".