21453263401 has 2 divisors, whose sum is σ = 21453263402. Its totient is φ = 21453263400.

The previous prime is 21453263389. The next prime is 21453263437. The reversal of 21453263401 is 10436235412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17212128025 + 4241135376 = 131195^2 + 65124^2 .

It is a cyclic number.

It is not a de Polignac number, because 21453263401 - 2⁹ = 21453262889 is a prime.

It is not a weakly prime, because it can be changed into another prime (21453263471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10726631700 + 10726631701.

It is an arithmetic number, because the mean of its divisors is an integer number (10726631701).

Almost surely, 2^21453263401 is an apocalyptic number.

It is an amenable number.

21453263401 is a deficient number, since it is larger than the sum of its proper divisors (1).

21453263401 is an equidigital number, since it uses as much as digits as its factorization.

21453263401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17280, while the sum is 31.

Adding to 21453263401 its reverse (10436235412), we get a palindrome (31889498813).

The spelling of 21453263401 in words is "twenty-one billion, four hundred fifty-three million, two hundred sixty-three thousand, four hundred one".