11111221220220 has 120 divisors (see below), whose sum is σ = 38025068236848. Its totient is φ = 2693629382400.

The previous prime is 11111221220171. The next prime is 11111221220237. The reversal of 11111221220220 is 2202212211111.

11111221220220 is a `hidden beast` number, since 1 + 1 + 1 + 1 + 1 + 221 + 220 + 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 = 11111221220193 and 11111221220202.

It is a congruent number.

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, 311744841 + ... + 311780480.

Almost surely, 2^{11111221220220} is an apocalyptic number.

11111221220220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11111221220220 is an abundant number, since it is smaller than the sum of its proper divisors (26913847016628).

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

11111221220220 is a wasteful number, since it uses less digits than its factorization.

11111221220220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 623525353 (or 623525342 counting only the distinct ones).

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

Adding to 11111221220220 its reverse (2202212211111), we get a palindrome (13313433431331).

The spelling of 11111221220220 in words is "eleven trillion, one hundred eleven billion, two hundred twenty-one million, two hundred twenty thousand, two hundred twenty".