1011112212221 has 4 divisors (see below), whose sum is σ = 1011168625500. Its totient is φ = 1011055798944.

The previous prime is 1011112212193. The next prime is 1011112212223. The reversal of 1011112212221 is 1222122111101.

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 798987487321 + 212124724900 = 893861^2 + 460570^2 .

It is a cyclic number.

It is not a de Polignac number, because 1011112212221 - 2²² = 1011108017917 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1011112212221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1011112212223) 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, 28179746 + ... + 28215603.

It is an arithmetic number, because the mean of its divisors is an integer number (252792156375).

Almost surely, 2^{1011112212221} is an apocalyptic number.

It is an amenable number.

1011112212221 is a deficient number, since it is larger than the sum of its proper divisors (56413279).

1011112212221 is an equidigital number, since it uses as much as digits as its factorization.

1011112212221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56413278.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 1011112212221 its reverse (1222122111101), we get a palindrome (2233234323322).

The spelling of 1011112212221 in words is "one trillion, eleven billion, one hundred twelve million, two hundred twelve thousand, two hundred twenty-one".