111020021221 has 4 divisors (see below), whose sum is σ = 111020707072. Its totient is φ = 111019335372.

The previous prime is 111020021191. The next prime is 111020021227. The reversal of 111020021221 is 122120020111.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-111020021221 is a prime.

It is a super-2 number, since 2×111020021221² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111020021227) 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, 49810 + ... + 473836.

It is an arithmetic number, because the mean of its divisors is an integer number (27755176768).

Almost surely, 2^111020021221 is an apocalyptic number.

It is an amenable number.

111020021221 is a deficient number, since it is larger than the sum of its proper divisors (685851).

111020021221 is an equidigital number, since it uses as much as digits as its factorization.

111020021221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 685850.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 111020021221 its reverse (122120020111), we get a palindrome (233140041332).

The spelling of 111020021221 in words is "one hundred eleven billion, twenty million, twenty-one thousand, two hundred twenty-one".