252809281 has 4 divisors (see below), whose sum is σ = 253633072. Its totient is φ = 251985492.

The previous prime is 252809273. The next prime is 252809339. The reversal of 252809281 is 182908252.

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 252809281 - 2³ = 252809273 is a prime.

It is a super-2 number, since 2×252809281² = 127825065119473922, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 252809281.

It is not an unprimeable number, because it can be changed into a prime (252879281) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 411435 + ... + 412048.

It is an arithmetic number, because the mean of its divisors is an integer number (63408268).

Almost surely, 2^252809281 is an apocalyptic number.

It is an amenable number.

252809281 is a deficient number, since it is larger than the sum of its proper divisors (823791).

252809281 is an equidigital number, since it uses as much as digits as its factorization.

252809281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 823790.

The product of its (nonzero) digits is 23040, while the sum is 37.

The square root of 252809281 is about 15899.9773899210. The cubic root of 252809281 is about 632.3113893401.

The spelling of 252809281 in words is "two hundred fifty-two million, eight hundred nine thousand, two hundred eighty-one".