111111100122221 has 8 divisors (see below), whose sum is σ = 117647157047544. Its totient is φ = 104575055403520.

The previous prime is 111111100122203. The next prime is 111111100122229. The reversal of 111111100122221 is 122221001111111.

It can be written as a sum of positive squares in 4 ways, for example, as 33510610657225 + 77600489464996 = 5788835^2 + 8809114^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 111111100122221 - 2³⁴ = 111093920253037 is a prime.

It is a super-2 number, since 2×111111100122221² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 111111100122221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111111100122229) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21191681 + ... + 25909641.

It is an arithmetic number, because the mean of its divisors is an integer number (14705894630943).

Almost surely, 2^{111111100122221} is an apocalyptic number.

It is an amenable number.

111111100122221 is a deficient number, since it is larger than the sum of its proper divisors (6536056925323).

111111100122221 is a wasteful number, since it uses less digits than its factorization.

111111100122221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6103311.

The product of its (nonzero) digits is 16, while the sum is 17.

Adding to 111111100122221 its reverse (122221001111111), we get a palindrome (233332101233332).

The spelling of 111111100122221 in words is "one hundred eleven trillion, one hundred eleven billion, one hundred million, one hundred twenty-two thousand, two hundred twenty-one".