252135809 has 2 divisors, whose sum is σ = 252135810. Its totient is φ = 252135808.

The previous prime is 252135799. The next prime is 252135811. The reversal of 252135809 is 908531252.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 241895809 + 10240000 = 15553^2 + 3200^2 .

It is a cyclic number.

It is not a de Polignac number, because 252135809 - 2²⁰ = 251087233 is a prime.

Together with 252135811, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (252135859) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 126067904 + 126067905.

It is an arithmetic number, because the mean of its divisors is an integer number (126067905).

Almost surely, 2^252135809 is an apocalyptic number.

It is an amenable number.

252135809 is a deficient number, since it is larger than the sum of its proper divisors (1).

252135809 is an equidigital number, since it uses as much as digits as its factorization.

252135809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21600, while the sum is 35.

The square root of 252135809 is about 15878.7848716456. The cubic root of 252135809 is about 631.7494074412.

The spelling of 252135809 in words is "two hundred fifty-two million, one hundred thirty-five thousand, eight hundred nine".