21255265535453 has 2 divisors, whose sum is σ = 21255265535454. Its totient is φ = 21255265535452.

The previous prime is 21255265535437. The next prime is 21255265535479. The reversal of 21255265535453 is 35453556255212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20392070314564 + 863195220889 = 4515758^2 + 929083^2 .

It is a cyclic number.

It is not a de Polignac number, because 21255265535453 - 2⁴ = 21255265535437 is a prime.

It is a super-2 number, since 2×21255265535453² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21255265535395 and 21255265535404.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21255265535753) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10627632767726 + 10627632767727.

It is an arithmetic number, because the mean of its divisors is an integer number (10627632767727).

Almost surely, 2^{21255265535453} is an apocalyptic number.

It is an amenable number.

21255265535453 is a deficient number, since it is larger than the sum of its proper divisors (1).

21255265535453 is an equidigital number, since it uses as much as digits as its factorization.

21255265535453 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27000000, while the sum is 53.

The spelling of 21255265535453 in words is "twenty-one trillion, two hundred fifty-five billion, two hundred sixty-five million, five hundred thirty-five thousand, four hundred fifty-three".