31156117 has 2 divisors, whose sum is σ = 31156118. Its totient is φ = 31156116.

The previous prime is 31156093. The next prime is 31156157. The reversal of 31156117 is 71165113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 30371121 + 784996 = 5511^2 + 886^2 .

It is a cyclic number.

It is not a de Polignac number, because 31156117 - 2⁷ = 31155989 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31156091 and 31156100.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31156157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15578058 + 15578059.

It is an arithmetic number, because the mean of its divisors is an integer number (15578059).

Almost surely, 2^31156117 is an apocalyptic number.

It is an amenable number.

31156117 is a deficient number, since it is larger than the sum of its proper divisors (1).

31156117 is an equidigital number, since it uses as much as digits as its factorization.

31156117 is an evil number, because the sum of its binary digits is even.

The product of its digits is 630, while the sum is 25.

The square root of 31156117 is about 5581.7664766631. The cubic root of 31156117 is about 314.6645189564.

The spelling of 31156117 in words is "thirty-one million, one hundred fifty-six thousand, one hundred seventeen".