1111111221220 has 384 divisors, whose sum is σ = 3231083520000. Its totient is φ = 309812428800.

The previous prime is 1111111221211. The next prime is 1111111221223. The reversal of 1111111221220 is 221221111111.

It is a junction number, because it is equal to n+sod(n) for n = 1111111221194 and 1111111221203.

It is not an unprimeable number, because it can be changed into a prime (1111111221223) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 83857156 + ... + 83870404.

It is an arithmetic number, because the mean of its divisors is an integer number (8414280000).

Almost surely, 2^{1111111221220} is an apocalyptic number.

1111111221220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1111111221220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1615541760000).

1111111221220 is an abundant number, since it is smaller than the sum of its proper divisors (2119972298780).

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

1111111221220 is a wasteful number, since it uses less digits than its factorization.

1111111221220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13419 (or 13417 counting only the distinct ones).

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

Adding to 1111111221220 its reverse (221221111111), we get a palindrome (1332332332331).

It can be divided in two parts, 1111111 and 221220, that added together give a palindrome (1332331).

The spelling of 1111111221220 in words is "one trillion, one hundred eleven billion, one hundred eleven million, two hundred twenty-one thousand, two hundred twenty".