253321821 has 24 divisors (see below), whose sum is σ = 381935736. Its totient is φ = 161640960.

The previous prime is 253321819. The next prime is 253321829. The reversal of 253321821 is 128123352.

It can be written as a sum of positive squares in 4 ways, for example, as 34596 + 253287225 = 186^2 + 15915^2 .

It is not a de Polignac number, because 253321821 - 2¹ = 253321819 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (253321829) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13081 + ... + 26033.

It is an arithmetic number, because the mean of its divisors is an integer number (15913989).

Almost surely, 2^253321821 is an apocalyptic number.

It is an amenable number.

253321821 is a deficient number, since it is larger than the sum of its proper divisors (128613915).

253321821 is a wasteful number, since it uses less digits than its factorization.

253321821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13053 (or 13050 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 253321821 is about 15916.0868620399. The cubic root of 253321821 is about 632.7384123122.

The spelling of 253321821 in words is "two hundred fifty-three million, three hundred twenty-one thousand, eight hundred twenty-one".