31004431 has 2 divisors, whose sum is σ = 31004432. Its totient is φ = 31004430.

The previous prime is 31004423. The next prime is 31004453. The reversal of 31004431 is 13440013.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31004431 - 2³ = 31004423 is a prime.

It is a super-2 number, since 2×31004431² = 1922549483267522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31004471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15502215 + 15502216.

It is an arithmetic number, because the mean of its divisors is an integer number (15502216).

Almost surely, 2^31004431 is an apocalyptic number.

31004431 is a deficient number, since it is larger than the sum of its proper divisors (1).

31004431 is an equidigital number, since it uses as much as digits as its factorization.

31004431 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 31004431 is about 5568.1622641586. The cubic root of 31004431 is about 314.1530316849.

Adding to 31004431 its reverse (13440013), we get a palindrome (44444444).

The spelling of 31004431 in words is "thirty-one million, four thousand, four hundred thirty-one".