161257 has 6 divisors (see below), whose sum is σ = 167018. Its totient is φ = 155664.

The previous prime is 161237. The next prime is 161263. The reversal of 161257 is 752161.

It can be written as a sum of positive squares in only one way, i.e., 141376 + 19881 = 376^2 + 141^2 .

It is not a de Polignac number, because 161257 - 2¹¹ = 159209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2173 + ... + 2245.

2¹⁶¹²⁵⁷ is an apocalyptic number.

It is an amenable number.

161257 is a deficient number, since it is larger than the sum of its proper divisors (5761).

161257 is an frugal number, since it uses more digits than its factorization.

161257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167 (or 120 counting only the distinct ones).

The product of its digits is 420, while the sum is 22.

The square root of 161257 is about 401.5681760299. The cubic root of 161257 is about 54.4301492696.

The spelling of 161257 in words is "one hundred sixty-one thousand, two hundred fifty-seven".