257171969 has 2 divisors, whose sum is σ = 257171970. Its totient is φ = 257171968.

The previous prime is 257171923. The next prime is 257171977. The reversal of 257171969 is 969171752.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 229219600 + 27952369 = 15140^2 + 5287^2 .

It is a cyclic number.

It is not a de Polignac number, because 257171969 - 2⁸ = 257171713 is a prime.

It is a super-2 number, since 2×257171969² = 132274843278673922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (257171909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128585984 + 128585985.

It is an arithmetic number, because the mean of its divisors is an integer number (128585985).

Almost surely, 2^257171969 is an apocalyptic number.

It is an amenable number.

257171969 is a deficient number, since it is larger than the sum of its proper divisors (1).

257171969 is an equidigital number, since it uses as much as digits as its factorization.

257171969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 238140, while the sum is 47.

The square root of 257171969 is about 16036.5822106832. The cubic root of 257171969 is about 635.9278963457.

The spelling of 257171969 in words is "two hundred fifty-seven million, one hundred seventy-one thousand, nine hundred sixty-nine".