21204110099 has 2 divisors, whose sum is σ = 21204110100. Its totient is φ = 21204110098.

The previous prime is 21204110063. The next prime is 21204110117. The reversal of 21204110099 is 99001140212.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21204110099 is a prime.

It is a super-2 number, since 2×21204110099² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21204110009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10602055049 + 10602055050.

It is an arithmetic number, because the mean of its divisors is an integer number (10602055050).

Almost surely, 2^21204110099 is an apocalyptic number.

21204110099 is a deficient number, since it is larger than the sum of its proper divisors (1).

21204110099 is an equidigital number, since it uses as much as digits as its factorization.

21204110099 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 29.

The spelling of 21204110099 in words is "twenty-one billion, two hundred four million, one hundred ten thousand, ninety-nine".