21111021121099 has 16 divisors (see below), whose sum is σ = 26127950526720. Its totient is φ = 16609911380640.

The previous prime is 21111021121087. The next prime is 21111021121117. The reversal of 21111021121099 is 99012112011112.

It is a cyclic number.

It is not a de Polignac number, because 21111021121099 - 2⁷ = 21111021120971 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21111021121099.

It is not an unprimeable number, because it can be changed into a prime (21111021121049) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 647998357 + ... + 648030934.

It is an arithmetic number, because the mean of its divisors is an integer number (1632996907920).

Almost surely, 2^{21111021121099} is an apocalyptic number.

21111021121099 is a deficient number, since it is larger than the sum of its proper divisors (5016929405621).

21111021121099 is a wasteful number, since it uses less digits than its factorization.

21111021121099 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1296029490.

The product of its (nonzero) digits is 648, while the sum is 31.

The spelling of 21111021121099 in words is "twenty-one trillion, one hundred eleven billion, twenty-one million, one hundred twenty-one thousand, ninety-nine".