252759726699561 has 45 divisors (see below), whose sum is σ = 388068126932871. Its totient is φ = 163948821097968.

The previous prime is 252759726699553. The next prime is 252759726699589. The reversal of 252759726699561 is 165996627957252.

The square root of 252759726699561 is 15898419.

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

252759726699561 is a `hidden beast` number, since 2 + 5 + 27 + 5 + 9 + 7 + 26 + 6 + 9 + 9 + 561 = 666.

252759726699561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 226172874512025 + 26586852187536 = 15039045^2 + 5156244^2 .

It is not a de Polignac number, because 252759726699561 - 2³ = 252759726699553 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is not an unprimeable number, because it can be changed into a prime (252759726649561) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 5294149656 + ... + 5294197398.

Almost surely, 2^{252759726699561} is an apocalyptic number.

252759726699561 is the 15898419-th square number.

252759726699561 is the 7949210-th centered octagonal number.

It is an amenable number.

252759726699561 is a deficient number, since it is larger than the sum of its proper divisors (135308400233310).

252759726699561 is an frugal number, since it uses more digits than its factorization.

252759726699561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95572 (or 47783 counting only the distinct ones).

The product of its digits is 7715736000, while the sum is 81.

252759726699561 divided by its sum of digits (81) gives a square (3120490453081 = 1766491²).

The spelling of 252759726699561 in words is "two hundred fifty-two trillion, seven hundred fifty-nine billion, seven hundred twenty-six million, six hundred ninety-nine thousand, five hundred sixty-one".