111221201221020 has 144 divisors (see below), whose sum is σ = 368233467874272. Its totient is φ = 26948620062720.

The previous prime is 111221201220959. The next prime is 111221201221021. The reversal of 111221201221020 is 20122102122111.

111221201221020 is a `hidden beast` number, since 1 + 1 + 1 + 221 + 201 + 221 + 0 + 20 = 666.

111221201221020 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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 = 111221201220984 and 111221201221002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111221201221021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 10893997 + ... + 18469476.

It is an arithmetic number, because the mean of its divisors is an integer number (2557176860238).

Almost surely, 2^{111221201221020} is an apocalyptic number.

111221201221020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

111221201221020 is an abundant number, since it is smaller than the sum of its proper divisors (257012266653252).

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

111221201221020 is a wasteful number, since it uses less digits than its factorization.

111221201221020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29365412 (or 29365407 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 111221201221020 its reverse (20122102122111), we get a palindrome (131343303343131).

The spelling of 111221201221020 in words is "one hundred eleven trillion, two hundred twenty-one billion, two hundred one million, two hundred twenty-one thousand, twenty".