161757172 has 6 divisors (see below), whose sum is σ = 283075058. Its totient is φ = 80878584.

The previous prime is 161757149. The next prime is 161757179. The reversal of 161757172 is 271757161.

It can be written as a sum of positive squares in only one way, i.e., 161696656 + 60516 = 12716^2 + 246^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161757179) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20219643 + ... + 20219650.

Almost surely, 2^161757172 is an apocalyptic number.

It is an amenable number.

161757172 is a deficient number, since it is larger than the sum of its proper divisors (121317886).

161757172 is a wasteful number, since it uses less digits than its factorization.

161757172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40439297 (or 40439295 counting only the distinct ones).

The product of its digits is 20580, while the sum is 37.

The square root of 161757172 is about 12718.3792992661. The cubic root of 161757172 is about 544.8636664849.

The spelling of 161757172 in words is "one hundred sixty-one million, seven hundred fifty-seven thousand, one hundred seventy-two".