256258128369 has 8 divisors (see below), whose sum is σ = 342910998400. Its totient is φ = 170222005296.

The previous prime is 256258128349. The next prime is 256258128397. The reversal of 256258128369 is 963821852652.

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

It is not a de Polignac number, because 256258128369 - 2⁷ = 256258128241 is a prime.

It is a super-2 number, since 2×256258128369² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256258128349) 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, 154185769 + ... + 154187430.

It is an arithmetic number, because the mean of its divisors is an integer number (42863874800).

Almost surely, 2^256258128369 is an apocalyptic number.

It is an amenable number.

256258128369 is a deficient number, since it is larger than the sum of its proper divisors (86652870031).

256258128369 is a wasteful number, since it uses less digits than its factorization.

256258128369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 308373479.

The product of its digits is 12441600, while the sum is 57.

The spelling of 256258128369 in words is "two hundred fifty-six billion, two hundred fifty-eight million, one hundred twenty-eight thousand, three hundred sixty-nine".