209145253 has 4 divisors (see below), whose sum is σ = 213595200. Its totient is φ = 204695308.

The previous prime is 209145229. The next prime is 209145263. The reversal of 209145253 is 352541902.

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 209145253 - 2⁵ = 209145221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209145263) 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, 2224903 + ... + 2224996.

It is an arithmetic number, because the mean of its divisors is an integer number (53398800).

Almost surely, 2^209145253 is an apocalyptic number.

It is an amenable number.

209145253 is a deficient number, since it is larger than the sum of its proper divisors (4449947).

209145253 is an equidigital number, since it uses as much as digits as its factorization.

209145253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4449946.

The product of its (nonzero) digits is 10800, while the sum is 31.

The square root of 209145253 is about 14461.8551023027. The cubic root of 209145253 is about 593.5846622481.

The spelling of 209145253 in words is "two hundred nine million, one hundred forty-five thousand, two hundred fifty-three".