31171980 has 48 divisors (see below), whose sum is σ = 99751680. Its totient is φ = 7124928.

The previous prime is 31171979. The next prime is 31171991. The reversal of 31171980 is 8917113.

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 15 ways as a sum of consecutive naturals, for example, 36690 + ... + 37529.

It is an arithmetic number, because the mean of its divisors is an integer number (2078160).

Almost surely, 2^31171980 is an apocalyptic number.

31171980 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

31171980 is an abundant number, since it is smaller than the sum of its proper divisors (68579700).

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

31171980 is a wasteful number, since it uses less digits than its factorization.

31171980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74238 (or 74236 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 30.

The square root of 31171980 is about 5583.1872617708. The cubic root of 31171980 is about 314.7179132477.

The spelling of 31171980 in words is "thirty-one million, one hundred seventy-one thousand, nine hundred eighty".