2100111111221 has 4 divisors (see below), whose sum is σ = 2100172253952. Its totient is φ = 2100049968492.

The previous prime is 2100111111211. The next prime is 2100111111317. The reversal of 2100111111221 is 1221111110012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2100111111221 is a prime.

It is a super-2 number, since 2×2100111111221² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2100111111196 and 2100111111205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2100111111211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30519815 + ... + 30588548.

It is an arithmetic number, because the mean of its divisors is an integer number (525043063488).

Almost surely, 2^{2100111111221} is an apocalyptic number.

It is an amenable number.

2100111111221 is a deficient number, since it is larger than the sum of its proper divisors (61142731).

2100111111221 is an equidigital number, since it uses as much as digits as its factorization.

2100111111221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61142730.

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 2100111111221 its reverse (1221111110012), we get a palindrome (3321222221233).

The spelling of 2100111111221 in words is "two trillion, one hundred billion, one hundred eleven million, one hundred eleven thousand, two hundred twenty-one".