21102021199 has 4 divisors (see below), whose sum is σ = 24116595664. Its totient is φ = 18087446736.

The previous prime is 21102021151. The next prime is 21102021211. The reversal of 21102021199 is 99112020112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21102021199 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21102021119) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1507287222 + ... + 1507287235.

It is an arithmetic number, because the mean of its divisors is an integer number (6029148916).

Almost surely, 2^21102021199 is an apocalyptic number.

21102021199 is a deficient number, since it is larger than the sum of its proper divisors (3014574465).

21102021199 is an equidigital number, since it uses as much as digits as its factorization.

21102021199 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3014574464.

The product of its (nonzero) digits is 648, while the sum is 28.

The spelling of 21102021199 in words is "twenty-one billion, one hundred two million, twenty-one thousand, one hundred ninety-nine".