257385961 has 4 divisors (see below), whose sum is σ = 294155392. Its totient is φ = 220616532.

The previous prime is 257385941. The next prime is 257385971. The reversal of 257385961 is 169583752.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 257385961 - 2⁵ = 257385929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (257385941) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18384705 + ... + 18384718.

It is an arithmetic number, because the mean of its divisors is an integer number (73538848).

Almost surely, 2^257385961 is an apocalyptic number.

It is an amenable number.

257385961 is a deficient number, since it is larger than the sum of its proper divisors (36769431).

257385961 is an equidigital number, since it uses as much as digits as its factorization.

257385961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36769430.

The product of its digits is 453600, while the sum is 46.

The square root of 257385961 is about 16043.2528185527. The cubic root of 257385961 is about 636.1042319906.

The spelling of 257385961 in words is "two hundred fifty-seven million, three hundred eighty-five thousand, nine hundred sixty-one".