31689113 has 2 divisors, whose sum is σ = 31689114. Its totient is φ = 31689112.

The previous prime is 31689089. The next prime is 31689137. The reversal of 31689113 is 31198613.

It is a balanced prime because it is at equal distance from previous prime (31689089) and next prime (31689137).

It can be written as a sum of positive squares in only one way, i.e., 25120144 + 6568969 = 5012^2 + 2563^2 .

It is an emirp because it is prime and its reverse (31198613) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31689113 - 2²⁰ = 30640537 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31689113.

It is not a weakly prime, because it can be changed into another prime (31689143) 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, 15844556 + 15844557.

It is an arithmetic number, because the mean of its divisors is an integer number (15844557).

Almost surely, 2^31689113 is an apocalyptic number.

It is an amenable number.

31689113 is a deficient number, since it is larger than the sum of its proper divisors (1).

31689113 is an equidigital number, since it uses as much as digits as its factorization.

31689113 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3888, while the sum is 32.

The square root of 31689113 is about 5629.3083944655. The cubic root of 31689113 is about 316.4487329061.

The spelling of 31689113 in words is "thirty-one million, six hundred eighty-nine thousand, one hundred thirteen".