252218561 has 4 divisors (see below), whose sum is σ = 288249792. Its totient is φ = 216187332.

The previous prime is 252218557. The next prime is 252218627. The reversal of 252218561 is 165812252.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 252218561 - 2² = 252218557 is a prime.

It is a super-2 number, since 2×252218561² = 127228405025821442, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (252218501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18015605 + ... + 18015618.

It is an arithmetic number, because the mean of its divisors is an integer number (72062448).

Almost surely, 2^252218561 is an apocalyptic number.

It is an amenable number.

252218561 is a deficient number, since it is larger than the sum of its proper divisors (36031231).

252218561 is an equidigital number, since it uses as much as digits as its factorization.

252218561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36031230.

The product of its digits is 9600, while the sum is 32.

The square root of 252218561 is about 15881.3903988284. The cubic root of 252218561 is about 631.8185141247.

The spelling of 252218561 in words is "two hundred fifty-two million, two hundred eighteen thousand, five hundred sixty-one".