21202111999 has 2 divisors, whose sum is σ = 21202112000. Its totient is φ = 21202111998.

The previous prime is 21202111993. The next prime is 21202112051. The reversal of 21202111999 is 99911120212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21202111999 - 2³ = 21202111991 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21202111991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10601055999 + 10601056000.

It is an arithmetic number, because the mean of its divisors is an integer number (10601056000).

Almost surely, 2^21202111999 is an apocalyptic number.

21202111999 is a deficient number, since it is larger than the sum of its proper divisors (1).

21202111999 is an equidigital number, since it uses as much as digits as its factorization.

21202111999 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5832, while the sum is 37.

The spelling of 21202111999 in words is "twenty-one billion, two hundred two million, one hundred eleven thousand, nine hundred ninety-nine".