21065453 has 2 divisors, whose sum is σ = 21065454. Its totient is φ = 21065452.

The previous prime is 21065437. The next prime is 21065459. The reversal of 21065453 is 35456012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20268004 + 797449 = 4502^2 + 893^2 .

It is a cyclic number.

It is not a de Polignac number, because 21065453 - 2⁴ = 21065437 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21065459) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10532726 + 10532727.

It is an arithmetic number, because the mean of its divisors is an integer number (10532727).

Almost surely, 2^21065453 is an apocalyptic number.

It is an amenable number.

21065453 is a deficient number, since it is larger than the sum of its proper divisors (1).

21065453 is an equidigital number, since it uses as much as digits as its factorization.

21065453 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3600, while the sum is 26.

The square root of 21065453 is about 4589.7116467159. The cubic root of 21065453 is about 276.1787550624.

The spelling of 21065453 in words is "twenty-one million, sixty-five thousand, four hundred fifty-three".