256979845449 has 48 divisors (see below), whose sum is σ = 410311558800. Its totient is φ = 154253611008.

The previous prime is 256979845439. The next prime is 256979845477. The reversal of 256979845449 is 944548979652.

256979845449 is a `hidden beast` number, since 2 + 5 + 6 + 9 + 79 + 8 + 4 + 544 + 9 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 82667750400 + 174312095049 = 287520^2 + 417507^2 .

It is not a de Polignac number, because 256979845449 - 2⁵ = 256979845417 is a prime.

It is a super-4 number, since 4×256979845449⁴ (a number of 47 digits) contains 4444 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (256979845439) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 217957 + ... + 749309.

It is an arithmetic number, because the mean of its divisors is an integer number (8548157475).

Almost surely, 2^256979845449 is an apocalyptic number.

256979845449 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

256979845449 is a deficient number, since it is larger than the sum of its proper divisors (153331713351).

256979845449 is a wasteful number, since it uses less digits than its factorization.

256979845449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 531514 (or 531511 counting only the distinct ones).

The product of its digits is 783820800, while the sum is 72.

The spelling of 256979845449 in words is "two hundred fifty-six billion, nine hundred seventy-nine million, eight hundred forty-five thousand, four hundred forty-nine".