111211112212221 has 64 divisors (see below), whose sum is σ = 170727358464000. Its totient is φ = 63077494265856.

The previous prime is 111211112212201. The next prime is 111211112212229. The reversal of 111211112212221 is 122212211112111.

It is not a de Polignac number, because 111211112212221 - 2⁷ = 111211112212093 is a prime.

It is a super-2 number, since 2×111211112212221² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111211112212229) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 7863325476 + ... + 7863339618.

It is an arithmetic number, because the mean of its divisors is an integer number (2667614976000).

Almost surely, 2^{111211112212221} is an apocalyptic number.

It is an amenable number.

111211112212221 is a deficient number, since it is larger than the sum of its proper divisors (59516246251779).

111211112212221 is a wasteful number, since it uses less digits than its factorization.

111211112212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19378.

The product of its digits is 64, while the sum is 21.

Adding to 111211112212221 its reverse (122212211112111), we get a palindrome (233423323324332).

The spelling of 111211112212221 in words is "one hundred eleven trillion, two hundred eleven billion, one hundred twelve million, two hundred twelve thousand, two hundred twenty-one".