257864081 has 4 divisors (see below), whose sum is σ = 257897712. Its totient is φ = 257830452.

The previous prime is 257864053. The next prime is 257864083. The reversal of 257864081 is 180468752.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 257864081 - 2¹⁰ = 257863057 is a prime.

It is a super-2 number, since 2×257864081² = 132987768539949122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (257864083) 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, 926 + ... + 22728.

It is an arithmetic number, because the mean of its divisors is an integer number (64474428).

Almost surely, 2^257864081 is an apocalyptic number.

It is an amenable number.

257864081 is a deficient number, since it is larger than the sum of its proper divisors (33631).

257864081 is a wasteful number, since it uses less digits than its factorization.

257864081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33630.

The product of its (nonzero) digits is 107520, while the sum is 41.

The square root of 257864081 is about 16058.1468731607. The cubic root of 257864081 is about 636.4978639619.

The spelling of 257864081 in words is "two hundred fifty-seven million, eight hundred sixty-four thousand, eighty-one".