257123161 has 2 divisors, whose sum is σ = 257123162. Its totient is φ = 257123160.

The previous prime is 257123159. The next prime is 257123171. The reversal of 257123161 is 161321752.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 257121225 + 1936 = 16035^2 + 44^2 .

It is a cyclic number.

It is not a de Polignac number, because 257123161 - 2¹ = 257123159 is a prime.

It is a super-2 number, since 2×257123161² = 132224639845263842, which contains 22 as substring.

Together with 257123159, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (257123171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128561580 + 128561581.

It is an arithmetic number, because the mean of its divisors is an integer number (128561581).

Almost surely, 2^257123161 is an apocalyptic number.

It is an amenable number.

257123161 is a deficient number, since it is larger than the sum of its proper divisors (1).

257123161 is an equidigital number, since it uses as much as digits as its factorization.

257123161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2520, while the sum is 28.

The square root of 257123161 is about 16035.0603678315. The cubic root of 257123161 is about 635.8876634325.

The spelling of 257123161 in words is "two hundred fifty-seven million, one hundred twenty-three thousand, one hundred sixty-one".