21100111220211 has 8 divisors (see below), whose sum is σ = 28134628485840. Its totient is φ = 14066167384032.

The previous prime is 21100111220197. The next prime is 21100111220261. The reversal of 21100111220211 is 11202211100112.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-21100111220211 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21100111220261) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 143271496 + ... + 143418693.

It is an arithmetic number, because the mean of its divisors is an integer number (3516828560730).

Almost surely, 2^{21100111220211} is an apocalyptic number.

21100111220211 is a deficient number, since it is larger than the sum of its proper divisors (7034517265629).

21100111220211 is a wasteful number, since it uses less digits than its factorization.

21100111220211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 286714725.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21100111220211 its reverse (11202211100112), we get a palindrome (32302322320323).

The spelling of 21100111220211 in words is "twenty-one trillion, one hundred billion, one hundred eleven million, two hundred twenty thousand, two hundred eleven".