12111221211220 has 96 divisors (see below), whose sum is σ = 25993725357600. Its totient is φ = 4738693693440.

The previous prime is 12111221211217. The next prime is 12111221211247. The reversal of 12111221211220 is 2211212211121.

It is a happy number.

It can be written as a sum of positive squares in 16 ways, for example, as 175564352016 + 11935656859204 = 419004^2 + 3454802^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 580891356 + ... + 580912204.

It is an arithmetic number, because the mean of its divisors is an integer number (270767972475).

Almost surely, 2^{12111221211220} is an apocalyptic number.

12111221211220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12111221211220 is an abundant number, since it is smaller than the sum of its proper divisors (13882504146380).

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

12111221211220 is a wasteful number, since it uses less digits than its factorization.

12111221211220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23533 (or 23531 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 12111221211220 its reverse (2211212211121), we get a palindrome (14322433422341).

Subtracting from 12111221211220 its reverse (2211212211121), we obtain a palindrome (9900009000099).

The spelling of 12111221211220 in words is "twelve trillion, one hundred eleven billion, two hundred twenty-one million, two hundred eleven thousand, two hundred twenty".