31609117 has 2 divisors, whose sum is σ = 31609118. Its totient is φ = 31609116.

The previous prime is 31609111. The next prime is 31609189. The reversal of 31609117 is 71190613.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19456921 + 12152196 = 4411^2 + 3486^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31609117 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31609111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15804558 + 15804559.

It is an arithmetic number, because the mean of its divisors is an integer number (15804559).

Almost surely, 2^31609117 is an apocalyptic number.

It is an amenable number.

31609117 is a deficient number, since it is larger than the sum of its proper divisors (1).

31609117 is an equidigital number, since it uses as much as digits as its factorization.

31609117 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1134, while the sum is 28.

The square root of 31609117 is about 5622.1985912986. The cubic root of 31609117 is about 316.1822274537.

The spelling of 31609117 in words is "thirty-one million, six hundred nine thousand, one hundred seventeen".