253421765 has 4 divisors (see below), whose sum is σ = 304106124. Its totient is φ = 202737408.

The previous prime is 253421759. The next prime is 253421767. The reversal of 253421765 is 567124352.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 171138724 + 82283041 = 13082^2 + 9071^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-253421765 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 (253421767) 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, 25342172 + ... + 25342181.

It is an arithmetic number, because the mean of its divisors is an integer number (76026531).

Almost surely, 2^253421765 is an apocalyptic number.

It is an amenable number.

253421765 is a deficient number, since it is larger than the sum of its proper divisors (50684359).

253421765 is an equidigital number, since it uses as much as digits as its factorization.

253421765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50684358.

The product of its digits is 50400, while the sum is 35.

The square root of 253421765 is about 15919.2262688863. The cubic root of 253421765 is about 632.8216135841.

The spelling of 253421765 in words is "two hundred fifty-three million, four hundred twenty-one thousand, seven hundred sixty-five".