256161217 has 8 divisors (see below), whose sum is σ = 276119424. Its totient is φ = 236239248.

The previous prime is 256161203. The next prime is 256161221. The reversal of 256161217 is 712161652.

256161217 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 256161217 - 2²⁷ = 121943489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256161617) 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, 6648 + ... + 23590.

It is an arithmetic number, because the mean of its divisors is an integer number (34514928).

Almost surely, 2^256161217 is an apocalyptic number.

It is an amenable number.

256161217 is a deficient number, since it is larger than the sum of its proper divisors (19958207).

256161217 is a wasteful number, since it uses less digits than its factorization.

256161217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18119.

The product of its digits is 5040, while the sum is 31.

The square root of 256161217 is about 16005.0372383197. The cubic root of 256161217 is about 635.0936824190.

The spelling of 256161217 in words is "two hundred fifty-six million, one hundred sixty-one thousand, two hundred seventeen".