257191917841 has 2 divisors, whose sum is σ = 257191917842. Its totient is φ = 257191917840.

The previous prime is 257191917799. The next prime is 257191917859. The reversal of 257191917841 is 148719191752.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 209086707600 + 48105210241 = 457260^2 + 219329^2 .

It is a cyclic number.

It is not a de Polignac number, because 257191917841 - 2⁹ = 257191917329 is a prime.

It is a super-2 number, since 2×257191917841² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (257191917881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128595958920 + 128595958921.

It is an arithmetic number, because the mean of its divisors is an integer number (128595958921).

Almost surely, 2^257191917841 is an apocalyptic number.

It is an amenable number.

257191917841 is a deficient number, since it is larger than the sum of its proper divisors (1).

257191917841 is an equidigital number, since it uses as much as digits as its factorization.

257191917841 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1270080, while the sum is 55.

The spelling of 257191917841 in words is "two hundred fifty-seven billion, one hundred ninety-one million, nine hundred seventeen thousand, eight hundred forty-one".