31923140 has 24 divisors (see below), whose sum is σ = 67155480. Its totient is φ = 12747008.

The previous prime is 31923139. The next prime is 31923163. The reversal of 31923140 is 4132913.

It can be written as a sum of positive squares in 4 ways, for example, as 4528384 + 27394756 = 2128^2 + 5234^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15194 + ... + 17166.

It is an arithmetic number, because the mean of its divisors is an integer number (2798145).

Almost surely, 2^31923140 is an apocalyptic number.

It is an amenable number.

31923140 is an abundant number, since it is smaller than the sum of its proper divisors (35232340).

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

31923140 is a wasteful number, since it uses less digits than its factorization.

31923140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2791 (or 2789 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 23.

The square root of 31923140 is about 5650.0566368843. The cubic root of 31923140 is about 317.2258240233.

The spelling of 31923140 in words is "thirty-one million, nine hundred twenty-three thousand, one hundred forty".