221212122111200 has 144 divisors (see below), whose sum is σ = 589137752770560. Its totient is φ = 80439453888000.

The previous prime is 221212122111179. The next prime is 221212122111269. The reversal of 221212122111200 is 2111221212122.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 655704161 + ... + 656041439.

It is an arithmetic number, because the mean of its divisors is an integer number (4091234394240).

Almost surely, 2^{221212122111200} is an apocalyptic number.

221212122111200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221212122111200 is an abundant number, since it is smaller than the sum of its proper divisors (367925630659360).

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

221212122111200 is a wasteful number, since it uses less digits than its factorization.

221212122111200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 411841 (or 411828 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 221212122111200 its reverse (2111221212122), we get a palindrome (223323343323322).

The spelling of 221212122111200 in words is "two hundred twenty-one trillion, two hundred twelve billion, one hundred twenty-two million, one hundred eleven thousand, two hundred".