12111111021220 has 12 divisors (see below), whose sum is σ = 25433333144604. Its totient is φ = 4844444408480.

The previous prime is 12111111021181. The next prime is 12111111021277. The reversal of 12111111021220 is 2212011111121.

It can be written as a sum of positive squares in 2 ways, for example, as 5078685916836 + 7032425104384 = 2253594^2 + 2651872^2 .

It is a junction number, because it is equal to n+sod(n) for n = 12111111021194 and 12111111021203.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 302777775511 + ... + 302777775550.

It is an arithmetic number, because the mean of its divisors is an integer number (2119444428717).

Almost surely, 2^{12111111021220} is an apocalyptic number.

12111111021220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12111111021220 is an abundant number, since it is smaller than the sum of its proper divisors (13322222123384).

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

12111111021220 is a wasteful number, since it uses less digits than its factorization.

12111111021220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 605555551070 (or 605555551068 counting only the distinct ones).

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

Adding to 12111111021220 its reverse (2212011111121), we get a palindrome (14323122132341).

The spelling of 12111111021220 in words is "twelve trillion, one hundred eleven billion, one hundred eleven million, twenty-one thousand, two hundred twenty".