31617916865 has 4 divisors (see below), whose sum is σ = 37941500244. Its totient is φ = 25294333488.

The previous prime is 31617916861. The next prime is 31617916879. The reversal of 31617916865 is 56861971613.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15995166784 + 15622750081 = 126472^2 + 124991^2 .

It is a cyclic number.

It is not a de Polignac number, because 31617916865 - 2² = 31617916861 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31617916861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3161791682 + ... + 3161791691.

It is an arithmetic number, because the mean of its divisors is an integer number (9485375061).

Almost surely, 2^31617916865 is an apocalyptic number.

It is an amenable number.

31617916865 is a deficient number, since it is larger than the sum of its proper divisors (6323583379).

31617916865 is an equidigital number, since it uses as much as digits as its factorization.

31617916865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6323583378.

The product of its digits is 1632960, while the sum is 53.

The spelling of 31617916865 in words is "thirty-one billion, six hundred seventeen million, nine hundred sixteen thousand, eight hundred sixty-five".