161715857 has 2 divisors, whose sum is σ = 161715858. Its totient is φ = 161715856.

The previous prime is 161715839. The next prime is 161715877. The reversal of 161715857 is 758517161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 157351936 + 4363921 = 12544^2 + 2089^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161715857 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (161715817) 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, 80857928 + 80857929.

It is an arithmetic number, because the mean of its divisors is an integer number (80857929).

Almost surely, 2^161715857 is an apocalyptic number.

It is an amenable number.

161715857 is a deficient number, since it is larger than the sum of its proper divisors (1).

161715857 is an equidigital number, since it uses as much as digits as its factorization.

161715857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 58800, while the sum is 41.

The square root of 161715857 is about 12716.7549712967. The cubic root of 161715857 is about 544.8172739841.

The spelling of 161715857 in words is "one hundred sixty-one million, seven hundred fifteen thousand, eight hundred fifty-seven".