256879689889 has 9 divisors (see below), whose sum is σ = 266058279097. Its totient is φ = 248007578224.

The previous prime is 256879689883. The next prime is 256879689893. The reversal of 256879689889 is 988986978652.

It is a happy number.

The square root of 256879689889 is 506833.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 52929904225 + 203949785664 = 230065^2 + 451608^2 .

It is not a de Polignac number, because 256879689889 - 2⁹ = 256879689377 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256879689883) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 14689419 + ... + 14706895.

Almost surely, 2^256879689889 is an apocalyptic number.

256879689889 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

256879689889 is the 506833-rd square number.

256879689889 is the 253417-th centered octagonal number.

It is an amenable number.

256879689889 is a deficient number, since it is larger than the sum of its proper divisors (9178589208).

256879689889 is an frugal number, since it uses more digits than its factorization.

256879689889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35012 (or 17506 counting only the distinct ones).

The product of its digits is 7524679680, while the sum is 85.

The spelling of 256879689889 in words is "two hundred fifty-six billion, eight hundred seventy-nine million, six hundred eighty-nine thousand, eight hundred eighty-nine".