253044021 has 4 divisors (see below), whose sum is σ = 337392032. Its totient is φ = 168696012.

The previous prime is 253044019. The next prime is 253044023. The reversal of 253044021 is 120440352.

253044021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 an interprime number because it is at equal distance from previous prime (253044019) and next prime (253044023).

It is not a de Polignac number, because 253044021 - 2¹ = 253044019 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 (253044023) 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, 42174001 + ... + 42174006.

It is an arithmetic number, because the mean of its divisors is an integer number (84348008).

Almost surely, 2^253044021 is an apocalyptic number.

It is an amenable number.

253044021 is a deficient number, since it is larger than the sum of its proper divisors (84348011).

253044021 is an equidigital number, since it uses as much as digits as its factorization.

253044021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84348010.

The product of its (nonzero) digits is 960, while the sum is 21.

The square root of 253044021 is about 15907.3574486776. The cubic root of 253044021 is about 632.5070346617.

Adding to 253044021 its reverse (120440352), we get a palindrome (373484373).

The spelling of 253044021 in words is "two hundred fifty-three million, forty-four thousand, twenty-one".