221111110121220 has 120 divisors (see below), whose sum is σ = 756691354698048. Its totient is φ = 53602693358400.

The previous prime is 221111110121197. The next prime is 221111110121249. The reversal of 221111110121220 is 22121011111122.

It is a happy number.

221111110121220 is a `hidden beast` number, since 2 + 211 + 1 + 1 + 110 + 121 + 220 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 221111110121193 and 221111110121202.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 6203997616 + ... + 6204033255.

Almost surely, 2^{221111110121220} is an apocalyptic number.

221111110121220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221111110121220 is an abundant number, since it is smaller than the sum of its proper divisors (535580244576828).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221111110121220 is a wasteful number, since it uses less digits than its factorization.

221111110121220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12408030903 (or 12408030892 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 18.

Adding to 221111110121220 its reverse (22121011111122), we get a palindrome (243232121232342).

The spelling of 221111110121220 in words is "two hundred twenty-one trillion, one hundred eleven billion, one hundred ten million, one hundred twenty-one thousand, two hundred twenty".