257645383 has 2 divisors, whose sum is σ = 257645384. Its totient is φ = 257645382.

The previous prime is 257645369. The next prime is 257645413. The reversal of 257645383 is 383546752.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 257645383 - 2²¹ = 255548231 is a prime.

It is a super-2 number, since 2×257645383² = 132762286762433378, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (257645303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128822691 + 128822692.

It is an arithmetic number, because the mean of its divisors is an integer number (128822692).

Almost surely, 2^257645383 is an apocalyptic number.

257645383 is a deficient number, since it is larger than the sum of its proper divisors (1).

257645383 is an equidigital number, since it uses as much as digits as its factorization.

257645383 is an evil number, because the sum of its binary digits is even.

The product of its digits is 604800, while the sum is 43.

The square root of 257645383 is about 16051.3358634102. The cubic root of 257645383 is about 636.3178722643.

The spelling of 257645383 in words is "two hundred fifty-seven million, six hundred forty-five thousand, three hundred eighty-three".