252591813581 has 4 divisors (see below), whose sum is σ = 258752589564. Its totient is φ = 246431037600.

The previous prime is 252591813569. The next prime is 252591813611. The reversal of 252591813581 is 185318195252.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 149765130025 + 102826683556 = 386995^2 + 320666^2 .

It is a cyclic number.

It is not a de Polignac number, because 252591813581 - 2¹⁴ = 252591797197 is a prime.

It is a super-2 number, since 2×252591813581² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (252591813781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3080387930 + ... + 3080388011.

It is an arithmetic number, because the mean of its divisors is an integer number (64688147391).

Almost surely, 2^252591813581 is an apocalyptic number.

It is an amenable number.

252591813581 is a deficient number, since it is larger than the sum of its proper divisors (6160775983).

252591813581 is an equidigital number, since it uses as much as digits as its factorization.

252591813581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6160775982.

The product of its digits is 864000, while the sum is 50.

The spelling of 252591813581 in words is "two hundred fifty-two billion, five hundred ninety-one million, eight hundred thirteen thousand, five hundred eighty-one".