111111011122221 has 24 divisors (see below), whose sum is σ = 175344172189056. Its totient is φ = 67239947255040.

The previous prime is 111111011122217. The next prime is 111111011122261. The reversal of 111111011122221 is 122221110111111.

It is not a de Polignac number, because 111111011122221 - 2² = 111111011122217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 111111011122194 and 111111011122203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111111011122211) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 833762085 + ... + 833895338.

It is an arithmetic number, because the mean of its divisors is an integer number (7306007174544).

Almost surely, 2^{111111011122221} is an apocalyptic number.

111111011122221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

111111011122221 is a deficient number, since it is larger than the sum of its proper divisors (64233161066835).

111111011122221 is a wasteful number, since it uses less digits than its factorization.

111111011122221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1667658113 (or 1667658110 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 18.

Adding to 111111011122221 its reverse (122221110111111), we get a palindrome (233332121233332).

The spelling of 111111011122221 in words is "one hundred eleven trillion, one hundred eleven billion, eleven million, one hundred twenty-two thousand, two hundred twenty-one".