31504013 has 2 divisors, whose sum is σ = 31504014. Its totient is φ = 31504012.

The previous prime is 31503977. The next prime is 31504037. The reversal of 31504013 is 31040513.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 31214569 + 289444 = 5587^2 + 538^2 .

It is a cyclic number.

It is not a de Polignac number, because 31504013 - 2²⁰ = 30455437 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31503982 and 31504000.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31524013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15752006 + 15752007.

It is an arithmetic number, because the mean of its divisors is an integer number (15752007).

Almost surely, 2^31504013 is an apocalyptic number.

It is an amenable number.

31504013 is a deficient number, since it is larger than the sum of its proper divisors (1).

31504013 is an equidigital number, since it uses as much as digits as its factorization.

31504013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 31504013 is about 5612.8435752299. The cubic root of 31504013 is about 315.8313907160.

Adding to 31504013 its reverse (31040513), we get a palindrome (62544526).

The spelling of 31504013 in words is "thirty-one million, five hundred four thousand, thirteen".