1212220111220 has 48 divisors (see below), whose sum is σ = 2643890215680. Its totient is φ = 466527675264.

The previous prime is 1212220111217. The next prime is 1212220111229. The reversal of 1212220111220 is 221110222121.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212220111229) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10873319 + ... + 10984238.

It is an arithmetic number, because the mean of its divisors is an integer number (55081046160).

Almost surely, 2^{1212220111220} is an apocalyptic number.

1212220111220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1212220111220 is an abundant number, since it is smaller than the sum of its proper divisors (1431670104460).

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

1212220111220 is a wasteful number, since it uses less digits than its factorization.

1212220111220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21857672 (or 21857670 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 1212220111220 its reverse (221110222121), we get a palindrome (1433330333341).

The spelling of 1212220111220 in words is "one trillion, two hundred twelve billion, two hundred twenty million, one hundred eleven thousand, two hundred twenty".