257161 has 2 divisors, whose sum is σ = 257162. Its totient is φ = 257160.

The previous prime is 257141. The next prime is 257171. The reversal of 257161 is 161752.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 197136 + 60025 = 444^2 + 245^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-257161 is a prime.

It is a super-2 number, since 2×257161² = 132263559842, which contains 22 as substring.

It is a nialpdrome in base 8.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (257141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128580 + 128581.

It is an arithmetic number, because the mean of its divisors is an integer number (128581).

2²⁵⁷¹⁶¹ is an apocalyptic number.

It is an amenable number.

257161 is a deficient number, since it is larger than the sum of its proper divisors (1).

257161 is an equidigital number, since it uses as much as digits as its factorization.

257161 is an evil number, because the sum of its binary digits is even.

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

The square root of 257161 is about 507.1104416200. The cubic root of 257161 is about 63.5918854935.

The spelling of 257161 in words is "two hundred fifty-seven thousand, one hundred sixty-one".