257256707 has 4 divisors (see below), whose sum is σ = 259908936. Its totient is φ = 254604480.

The previous prime is 257256689. The next prime is 257256721. The reversal of 257256707 is 707652752.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 257256707 - 2²⁰ = 256208131 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (257256787) 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, 1325969 + ... + 1326162.

It is an arithmetic number, because the mean of its divisors is an integer number (64977234).

Almost surely, 2^257256707 is an apocalyptic number.

257256707 is a deficient number, since it is larger than the sum of its proper divisors (2652229).

257256707 is an equidigital number, since it uses as much as digits as its factorization.

257256707 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2652228.

The product of its (nonzero) digits is 205800, while the sum is 41.

The square root of 257256707 is about 16039.2240148955. The cubic root of 257256707 is about 635.9977346214.

The spelling of 257256707 in words is "two hundred fifty-seven million, two hundred fifty-six thousand, seven hundred seven".