31131404 has 6 divisors (see below), whose sum is σ = 54479964. Its totient is φ = 15565700.

The previous prime is 31131379. The next prime is 31131407. The reversal of 31131404 is 40413113.

It is a super-2 number, since 2×31131404² = 1938328630022432, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (31131407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3891422 + ... + 3891429.

It is an arithmetic number, because the mean of its divisors is an integer number (9079994).

Almost surely, 2^31131404 is an apocalyptic number.

It is an amenable number.

31131404 is a deficient number, since it is larger than the sum of its proper divisors (23348560).

31131404 is a wasteful number, since it uses less digits than its factorization.

31131404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7782855 (or 7782853 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 31131404 is about 5579.5523117899. The cubic root of 31131404 is about 314.5812997583.

Adding to 31131404 its reverse (40413113), we get a palindrome (71544517).

The spelling of 31131404 in words is "thirty-one million, one hundred thirty-one thousand, four hundred four".