2111122222021 has 4 divisors (see below), whose sum is σ = 2118327417612. Its totient is φ = 2103917026432.

The previous prime is 2111122222003. The next prime is 2111122222039. The reversal of 2111122222021 is 1202222211112.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (2111122222003) and next prime (2111122222039).

It can be written as a sum of positive squares in 2 ways, for example, as 1508696324100 + 602425897921 = 1228290^2 + 776161^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2111122222021 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2111122222021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2111122222421) 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, 3602597356 + ... + 3602597941.

It is an arithmetic number, because the mean of its divisors is an integer number (529581854403).

Almost surely, 2^{2111122222021} is an apocalyptic number.

It is an amenable number.

2111122222021 is a deficient number, since it is larger than the sum of its proper divisors (7205195591).

2111122222021 is an equidigital number, since it uses as much as digits as its factorization.

2111122222021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7205195590.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 2111122222021 its reverse (1202222211112), we get a palindrome (3313344433133).

The spelling of 2111122222021 in words is "two trillion, one hundred eleven billion, one hundred twenty-two million, two hundred twenty-two thousand, twenty-one".