111111110001221 has 64 divisors (see below), whose sum is σ = 132925605120000. Its totient is φ = 91740618144000.

The previous prime is 111111110001181. The next prime is 111111110001247. The reversal of 111111110001221 is 122100011111111.

It is a cyclic number.

It is not a de Polignac number, because 111111110001221 - 2³⁴ = 111093930132037 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 111111110001196 and 111111110001205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111111110001251) 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, 2113195910 + ... + 2113248488.

It is an arithmetic number, because the mean of its divisors is an integer number (2076962580000).

Almost surely, 2^{111111110001221} is an apocalyptic number.

111111110001221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

111111110001221 is a deficient number, since it is larger than the sum of its proper divisors (21814495118779).

111111110001221 is a wasteful number, since it uses less digits than its factorization.

111111110001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55098.

The product of its (nonzero) digits is 4, while the sum is 14.

Adding to 111111110001221 its reverse (122100011111111), we get a palindrome (233211121112332).

The spelling of 111111110001221 in words is "one hundred eleven trillion, one hundred eleven billion, one hundred ten million, one thousand, two hundred twenty-one".