21121099199 has 2 divisors, whose sum is σ = 21121099200. Its totient is φ = 21121099198.

The previous prime is 21121099189. The next prime is 21121099289. The reversal of 21121099199 is 99199012112.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21121099199 is a prime.

It is a super-2 number, since 2×21121099199² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21121099189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560549599 + 10560549600.

It is an arithmetic number, because the mean of its divisors is an integer number (10560549600).

Almost surely, 2^21121099199 is an apocalyptic number.

21121099199 is a deficient number, since it is larger than the sum of its proper divisors (1).

21121099199 is an equidigital number, since it uses as much as digits as its factorization.

21121099199 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 26244, while the sum is 44.

The spelling of 21121099199 in words is "twenty-one billion, one hundred twenty-one million, ninety-nine thousand, one hundred ninety-nine".