257356961 has 2 divisors, whose sum is σ = 257356962. Its totient is φ = 257356960.

The previous prime is 257356861. The next prime is 257356963. The reversal of 257356961 is 169653752.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 242580625 + 14776336 = 15575^2 + 3844^2 .

It is a cyclic number.

It is not a de Polignac number, because 257356961 - 2¹⁰ = 257355937 is a prime.

It is a Sophie Germain prime.

Together with 257356963, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (257356963) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128678480 + 128678481.

It is an arithmetic number, because the mean of its divisors is an integer number (128678481).

Almost surely, 2^257356961 is an apocalyptic number.

It is an amenable number.

257356961 is a deficient number, since it is larger than the sum of its proper divisors (1).

257356961 is an equidigital number, since it uses as much as digits as its factorization.

257356961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 340200, while the sum is 44.

The square root of 257356961 is about 16042.3489863548. The cubic root of 257356961 is about 636.0803408719.

The spelling of 257356961 in words is "two hundred fifty-seven million, three hundred fifty-six thousand, nine hundred sixty-one".