31253891 has 2 divisors, whose sum is σ = 31253892. Its totient is φ = 31253890.

The previous prime is 31253881. The next prime is 31253969. The reversal of 31253891 is 19835213.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31253891 is a prime.

It is not a weakly prime, because it can be changed into another prime (31253801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15626945 + 15626946.

It is an arithmetic number, because the mean of its divisors is an integer number (15626946).

Almost surely, 2^31253891 is an apocalyptic number.

31253891 is a deficient number, since it is larger than the sum of its proper divisors (1).

31253891 is an equidigital number, since it uses as much as digits as its factorization.

31253891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6480, while the sum is 32.

The square root of 31253891 is about 5590.5179545369. The cubic root of 31253891 is about 314.9933348720.

It can be divided in two parts, 3 and 1253891, that multiplied together give a palindrome (3761673).

The spelling of 31253891 in words is "thirty-one million, two hundred fifty-three thousand, eight hundred ninety-one".