12121211220 has 24 divisors (see below), whose sum is σ = 33939391584. Its totient is φ = 3232322976.

The previous prime is 12121211173. The next prime is 12121211233. The reversal of 12121211220 is 2211212121.

It is a super-2 number, since 2×12121211220² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 12121211220.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 101010034 + ... + 101010153.

It is an arithmetic number, because the mean of its divisors is an integer number (1414141316).

Almost surely, 2^12121211220 is an apocalyptic number.

12121211220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12121211220 is an abundant number, since it is smaller than the sum of its proper divisors (21818180364).

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

12121211220 is a wasteful number, since it uses less digits than its factorization.

12121211220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 202020199 (or 202020197 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 12121211220 its reverse (2211212121), we get a palindrome (14332423341).

Subtracting from 12121211220 its reverse (2211212121), we obtain a palindrome (9909999099).

The spelling of 12121211220 in words is "twelve billion, one hundred twenty-one million, two hundred eleven thousand, two hundred twenty".