161757971 has 2 divisors, whose sum is σ = 161757972. Its totient is φ = 161757970.

The previous prime is 161757943. The next prime is 161757977. The reversal of 161757971 is 179757161.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 161757971 - 2¹⁸ = 161495827 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (161757977) 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, 80878985 + 80878986.

It is an arithmetic number, because the mean of its divisors is an integer number (80878986).

Almost surely, 2^161757971 is an apocalyptic number.

161757971 is a deficient number, since it is larger than the sum of its proper divisors (1).

161757971 is an equidigital number, since it uses as much as digits as its factorization.

161757971 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 92610, while the sum is 44.

The square root of 161757971 is about 12718.4107104622. The cubic root of 161757971 is about 544.8645636020.

The spelling of 161757971 in words is "one hundred sixty-one million, seven hundred fifty-seven thousand, nine hundred seventy-one".