21453260953 has 2 divisors, whose sum is σ = 21453260954. Its totient is φ = 21453260952.

The previous prime is 21453260929. The next prime is 21453260963. The reversal of 21453260953 is 35906235412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14493029769 + 6960231184 = 120387^2 + 83428^2 .

It is a cyclic number.

It is not a de Polignac number, because 21453260953 - 2⁵ = 21453260921 is a prime.

It is not a weakly prime, because it can be changed into another prime (21453260903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10726630476 + 10726630477.

It is an arithmetic number, because the mean of its divisors is an integer number (10726630477).

Almost surely, 2^21453260953 is an apocalyptic number.

It is an amenable number.

21453260953 is a deficient number, since it is larger than the sum of its proper divisors (1).

21453260953 is an equidigital number, since it uses as much as digits as its factorization.

21453260953 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 194400, while the sum is 40.

The spelling of 21453260953 in words is "twenty-one billion, four hundred fifty-three million, two hundred sixty thousand, nine hundred fifty-three".