21424246253 has 2 divisors, whose sum is σ = 21424246254. Its totient is φ = 21424246252.

The previous prime is 21424246177. The next prime is 21424246297. The reversal of 21424246253 is 35264242412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12652425289 + 8771820964 = 112483^2 + 93658^2 .

It is a cyclic number.

It is not a de Polignac number, because 21424246253 - 2¹² = 21424242157 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21424246453) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10712123126 + 10712123127.

It is an arithmetic number, because the mean of its divisors is an integer number (10712123127).

Almost surely, 2^21424246253 is an apocalyptic number.

It is an amenable number.

21424246253 is a deficient number, since it is larger than the sum of its proper divisors (1).

21424246253 is an equidigital number, since it uses as much as digits as its factorization.

21424246253 is an evil number, because the sum of its binary digits is even.

The product of its digits is 92160, while the sum is 35.

Adding to 21424246253 its reverse (35264242412), we get a palindrome (56688488665).

The spelling of 21424246253 in words is "twenty-one billion, four hundred twenty-four million, two hundred forty-six thousand, two hundred fifty-three".