257705971 has 2 divisors, whose sum is σ = 257705972. Its totient is φ = 257705970.

The previous prime is 257705957. The next prime is 257705989. The reversal of 257705971 is 179507752.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 257705971 - 2⁵ = 257705939 is a prime.

It is not a weakly prime, because it can be changed into another prime (257705171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128852985 + 128852986.

It is an arithmetic number, because the mean of its divisors is an integer number (128852986).

Almost surely, 2^257705971 is an apocalyptic number.

257705971 is a deficient number, since it is larger than the sum of its proper divisors (1).

257705971 is an equidigital number, since it uses as much as digits as its factorization.

257705971 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 154350, while the sum is 43.

The square root of 257705971 is about 16053.2230720189. The cubic root of 257705971 is about 636.3677472839.

The spelling of 257705971 in words is "two hundred fifty-seven million, seven hundred five thousand, nine hundred seventy-one".