31113613 has 2 divisors, whose sum is σ = 31113614. Its totient is φ = 31113612.

The previous prime is 31113611. The next prime is 31113619. The reversal of 31113613 is 31631113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28281124 + 2832489 = 5318^2 + 1683^2 .

It is a cyclic number.

It is not a de Polignac number, because 31113613 - 2¹ = 31113611 is a prime.

Together with 31113611, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31113611) 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, 15556806 + 15556807.

It is an arithmetic number, because the mean of its divisors is an integer number (15556807).

Almost surely, 2^31113613 is an apocalyptic number.

It is an amenable number.

31113613 is a deficient number, since it is larger than the sum of its proper divisors (1).

31113613 is an equidigital number, since it uses as much as digits as its factorization.

31113613 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 162, while the sum is 19.

The square root of 31113613 is about 5577.9577804067. The cubic root of 31113613 is about 314.5213626138.

Adding to 31113613 its reverse (31631113), we get a palindrome (62744726).

It can be divided in two parts, 3111 and 3613, that added together give a square (6724 = 82²).

The spelling of 31113613 in words is "thirty-one million, one hundred thirteen thousand, six hundred thirteen".