221212221221200 has 240 divisors, whose sum is σ = 589158502067520. Its totient is φ = 79142164992000.

The previous prime is 221212221221197. The next prime is 221212221221207. The reversal of 221212221221200 is 2122122212122.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221212221221207) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 238029430 + ... + 238956970.

It is an arithmetic number, because the mean of its divisors is an integer number (2454827091948).

Almost surely, 2^{221212221221200} is an apocalyptic number.

221212221221200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221212221221200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (294579251033760).

221212221221200 is an abundant number, since it is smaller than the sum of its proper divisors (367946280846320).

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

221212221221200 is a wasteful number, since it uses less digits than its factorization.

221212221221200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 928446 (or 928435 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 22.

Adding to 221212221221200 its reverse (2122122212122), we get a palindrome (223334343433322).

The spelling of 221212221221200 in words is "two hundred twenty-one trillion, two hundred twelve billion, two hundred twenty-one million, two hundred twenty-one thousand, two hundred".