21753892609 has 2 divisors, whose sum is σ = 21753892610. Its totient is φ = 21753892608.

The previous prime is 21753892561. The next prime is 21753892649. The reversal of 21753892609 is 90629835712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15938305009 + 5815587600 = 126247^2 + 76260^2 .

It is a cyclic number.

It is not a de Polignac number, because 21753892609 - 2²⁹ = 21217021697 is a prime.

It is not a weakly prime, because it can be changed into another prime (21753892649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10876946304 + 10876946305.

It is an arithmetic number, because the mean of its divisors is an integer number (10876946305).

Almost surely, 2^21753892609 is an apocalyptic number.

It is an amenable number.

21753892609 is a deficient number, since it is larger than the sum of its proper divisors (1).

21753892609 is an equidigital number, since it uses as much as digits as its factorization.

21753892609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1632960, while the sum is 52.

The spelling of 21753892609 in words is "twenty-one billion, seven hundred fifty-three million, eight hundred ninety-two thousand, six hundred nine".