257661763 has 2 divisors, whose sum is σ = 257661764. Its totient is φ = 257661762.

The previous prime is 257661731. The next prime is 257661773. The reversal of 257661763 is 367166752.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 257661763 - 2⁵ = 257661731 is a prime.

It is a super-2 number, since 2×257661763² = 132779168224536338, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (257661773) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128830881 + 128830882.

It is an arithmetic number, because the mean of its divisors is an integer number (128830882).

Almost surely, 2^257661763 is an apocalyptic number.

257661763 is a deficient number, since it is larger than the sum of its proper divisors (1).

257661763 is an equidigital number, since it uses as much as digits as its factorization.

257661763 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 317520, while the sum is 43.

The square root of 257661763 is about 16051.8460932068. The cubic root of 257661763 is about 636.3313567751.

The spelling of 257661763 in words is "two hundred fifty-seven million, six hundred sixty-one thousand, seven hundred sixty-three".