31242920 has 32 divisors (see below), whose sum is σ = 71193600. Its totient is φ = 12337728.

The previous prime is 31242907. The next prime is 31242931. The reversal of 31242920 is 2924213.

It is a super-2 number, since 2×31242920² = 1952240100252800, which contains 22 as substring.

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, 1784 + ... + 8103.

It is an arithmetic number, because the mean of its divisors is an integer number (2224800).

Almost surely, 2^31242920 is an apocalyptic number.

It is an amenable number.

31242920 is an abundant number, since it is smaller than the sum of its proper divisors (39950680).

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

31242920 is a wasteful number, since it uses less digits than its factorization.

31242920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9977 (or 9973 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 31242920 is about 5589.5366534267. The cubic root of 31242920 is about 314.9564733677.

The spelling of 31242920 in words is "thirty-one million, two hundred forty-two thousand, nine hundred twenty".