111021211220 has 48 divisors (see below), whose sum is σ = 239147829648. Its totient is φ = 43267875840.

The previous prime is 111021211199. The next prime is 111021211243. The reversal of 111021211220 is 22112120111.

It can be written as a sum of positive squares in 8 ways, for example, as 6572020624 + 104449190596 = 81068^2 + 323186^2 .

It is a junction number, because it is equal to n+sod(n) for n = 111021211195 and 111021211204.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 531314 + ... + 710166.

It is an arithmetic number, because the mean of its divisors is an integer number (4982246451).

Almost surely, 2^111021211220 is an apocalyptic number.

111021211220 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 111021211220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (119573914824).

111021211220 is an abundant number, since it is smaller than the sum of its proper divisors (128126618428).

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

111021211220 is a wasteful number, since it uses less digits than its factorization.

111021211220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179660 (or 179658 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 111021211220 its reverse (22112120111), we get a palindrome (133133331331).

The spelling of 111021211220 in words is "one hundred eleven billion, twenty-one million, two hundred eleven thousand, two hundred twenty".