31157390 has 32 divisors (see below), whose sum is σ = 61624800. Its totient is φ = 11248000.

The previous prime is 31157333. The next prime is 31157393. The reversal of 31157390 is 9375113.

It is a super-2 number, since 2×31157390² = 1941565903224200, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31157393) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15440 + ... + 17340.

It is an arithmetic number, because the mean of its divisors is an integer number (1925775).

Almost surely, 2^31157390 is an apocalyptic number.

31157390 is a deficient number, since it is larger than the sum of its proper divisors (30467410).

31157390 is a wasteful number, since it uses less digits than its factorization.

31157390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2068.

The product of its (nonzero) digits is 2835, while the sum is 29.

The square root of 31157390 is about 5581.8805074992. The cubic root of 31157390 is about 314.6688044977.

The spelling of 31157390 in words is "thirty-one million, one hundred fifty-seven thousand, three hundred ninety".