31286880 has 72 divisors (see below), whose sum is σ = 106771392. Its totient is φ = 8342784.

The previous prime is 31286837. The next prime is 31286891. The reversal of 31286880 is 8868213.

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

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 11 ways as a sum of consecutive naturals, for example, 9424 + ... + 12303.

It is an arithmetic number, because the mean of its divisors is an integer number (1482936).

Almost surely, 2^31286880 is an apocalyptic number.

31286880 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

31286880 is an abundant number, since it is smaller than the sum of its proper divisors (75484512).

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

31286880 is a wasteful number, since it uses less digits than its factorization.

31286880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21748 (or 21737 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 31286880 is about 5593.4676185708. The cubic root of 31286880 is about 315.1041227970.

The spelling of 31286880 in words is "thirty-one million, two hundred eighty-six thousand, eight hundred eighty".