21552333449 has 2 divisors, whose sum is σ = 21552333450. Its totient is φ = 21552333448.

The previous prime is 21552333443. The next prime is 21552333461. The reversal of 21552333449 is 94433325512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16629907849 + 4922425600 = 128957^2 + 70160^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21552333449 is a prime.

It is a super-3 number, since 3×21552333449³ (a number of 32 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (21552333443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10776166724 + 10776166725.

It is an arithmetic number, because the mean of its divisors is an integer number (10776166725).

Almost surely, 2^21552333449 is an apocalyptic number.

It is an amenable number.

21552333449 is a deficient number, since it is larger than the sum of its proper divisors (1).

21552333449 is an equidigital number, since it uses as much as digits as its factorization.

21552333449 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 388800, while the sum is 41.

The spelling of 21552333449 in words is "twenty-one billion, five hundred fifty-two million, three hundred thirty-three thousand, four hundred forty-nine".