21006326599 has 2 divisors, whose sum is σ = 21006326600. Its totient is φ = 21006326598.

The previous prime is 21006326597. The next prime is 21006326633. The reversal of 21006326599 is 99562360012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21006326599 - 2¹ = 21006326597 is a prime.

Together with 21006326597, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21006326591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10503163299 + 10503163300.

It is an arithmetic number, because the mean of its divisors is an integer number (10503163300).

Almost surely, 2^21006326599 is an apocalyptic number.

21006326599 is a deficient number, since it is larger than the sum of its proper divisors (1).

21006326599 is an equidigital number, since it uses as much as digits as its factorization.

21006326599 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 174960, while the sum is 43.

The spelling of 21006326599 in words is "twenty-one billion, six million, three hundred twenty-six thousand, five hundred ninety-nine".