255569680521 has 15 divisors (see below), whose sum is σ = 381783726973. Its totient is φ = 170376753780.

The previous prime is 255569680501. The next prime is 255569680529. The reversal of 255569680521 is 125086965552.

It is a happy number.

The square root of 255569680521 is 505539.

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

255569680521 is a `hidden beast` number, since 2 + 5 + 5 + 56 + 9 + 68 + 0 + 521 = 666.

It is not a de Polignac number, because 255569680521 - 2⁷ = 255569680393 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (255569680529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 4521766 + ... + 4577936.

Almost surely, 2^255569680521 is an apocalyptic number.

255569680521 is the 505539-th square number.

255569680521 is the 252770-th centered octagonal number.

It is an amenable number.

255569680521 is a deficient number, since it is larger than the sum of its proper divisors (126214046452).

255569680521 is an frugal number, since it uses more digits than its factorization.

255569680521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112354 (or 56174 counting only the distinct ones).

The product of its (nonzero) digits is 6480000, while the sum is 54.

The spelling of 255569680521 in words is "two hundred fifty-five billion, five hundred sixty-nine million, six hundred eighty thousand, five hundred twenty-one".