21552303449 has 2 divisors, whose sum is σ = 21552303450. Its totient is φ = 21552303448.

The previous prime is 21552303413. The next prime is 21552303467. The reversal of 21552303449 is 94430325512.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12181095424 + 9371208025 = 110368^2 + 96805^2 .

It is a cyclic number.

It is not a de Polignac number, because 21552303449 - 2¹⁶ = 21552237913 is a prime.

It is not a weakly prime, because it can be changed into another prime (21552333449) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10776151724 + 10776151725.

It is an arithmetic number, because the mean of its divisors is an integer number (10776151725).

Almost surely, 2^21552303449 is an apocalyptic number.

It is an amenable number.

21552303449 is a deficient number, since it is larger than the sum of its proper divisors (1).

21552303449 is an equidigital number, since it uses as much as digits as its factorization.

21552303449 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 129600, while the sum is 38.

The spelling of 21552303449 in words is "twenty-one billion, five hundred fifty-two million, three hundred three thousand, four hundred forty-nine".