11112221212021 has 4 divisors (see below), whose sum is σ = 11113296633292. Its totient is φ = 11111145790752.

The previous prime is 11112221211989. The next prime is 11112221212051. The reversal of 11112221212021 is 12021212221111.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 9088114622500 + 2024106589521 = 3014650^2 + 1422711^2 .

It is a cyclic number.

It is not a de Polignac number, because 11112221212021 - 2⁵ = 11112221211989 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 11112221212021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11112221212051) 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, 537695136 + ... + 537715801.

It is an arithmetic number, because the mean of its divisors is an integer number (2778324158323).

Almost surely, 2^{11112221212021} is an apocalyptic number.

It is an amenable number.

11112221212021 is a deficient number, since it is larger than the sum of its proper divisors (1075421271).

11112221212021 is a wasteful number, since it uses less digits than its factorization.

11112221212021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1075421270.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 11112221212021 its reverse (12021212221111), we get a palindrome (23133433433132).

The spelling of 11112221212021 in words is "eleven trillion, one hundred twelve billion, two hundred twenty-one million, two hundred twelve thousand, twenty-one".