21202321099 has 2 divisors, whose sum is σ = 21202321100. Its totient is φ = 21202321098.

The previous prime is 21202321097. The next prime is 21202321123. The reversal of 21202321099 is 99012320212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21202321099 - 2¹ = 21202321097 is a prime.

Together with 21202321097, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21202321099.

It is not a weakly prime, because it can be changed into another prime (21202321097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10601160549 + 10601160550.

It is an arithmetic number, because the mean of its divisors is an integer number (10601160550).

Almost surely, 2^21202321099 is an apocalyptic number.

21202321099 is a deficient number, since it is larger than the sum of its proper divisors (1).

21202321099 is an equidigital number, since it uses as much as digits as its factorization.

21202321099 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3888, while the sum is 31.

The spelling of 21202321099 in words is "twenty-one billion, two hundred two million, three hundred twenty-one thousand, ninety-nine".