256430161 has 8 divisors (see below), whose sum is σ = 278173224. Its totient is φ = 234975360.

The previous prime is 256430147. The next prime is 256430177. The reversal of 256430161 is 161034652.

It can be written as a sum of positive squares in 4 ways, for example, as 18653761 + 237776400 = 4319^2 + 15420^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 256430161 - 2⁷ = 256430033 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256430191) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 70210 + ... + 73771.

It is an arithmetic number, because the mean of its divisors is an integer number (34771653).

Almost surely, 2^256430161 is an apocalyptic number.

It is an amenable number.

256430161 is a deficient number, since it is larger than the sum of its proper divisors (21743063).

256430161 is a wasteful number, since it uses less digits than its factorization.

256430161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 144131.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 256430161 is about 16013.4368890629. The cubic root of 256430161 is about 635.3158665785.

The spelling of 256430161 in words is "two hundred fifty-six million, four hundred thirty thousand, one hundred sixty-one".