21326057573 has 2 divisors, whose sum is σ = 21326057574. Its totient is φ = 21326057572.

The previous prime is 21326057569. The next prime is 21326057579. The reversal of 21326057573 is 37575062312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19004552449 + 2321505124 = 137857^2 + 48182^2 .

It is a cyclic number.

It is not a de Polignac number, because 21326057573 - 2² = 21326057569 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21326057573.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21326057579) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10663028786 + 10663028787.

It is an arithmetic number, because the mean of its divisors is an integer number (10663028787).

Almost surely, 2^21326057573 is an apocalyptic number.

It is an amenable number.

21326057573 is a deficient number, since it is larger than the sum of its proper divisors (1).

21326057573 is an equidigital number, since it uses as much as digits as its factorization.

21326057573 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 264600, while the sum is 41.

The spelling of 21326057573 in words is "twenty-one billion, three hundred twenty-six million, fifty-seven thousand, five hundred seventy-three".