21222221222200 has 192 divisors, whose sum is σ = 51567774228000. Its totient is φ = 8111980800000.

The previous prime is 21222221222087. The next prime is 21222221222207. The reversal of 21222221222200 is 222212222212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21222221222207) 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, 2143437250 + ... + 2143447150.

Almost surely, 2^{21222221222200} is an apocalyptic number.

21222221222200 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 21222221222200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25783887114000).

21222221222200 is an abundant number, since it is smaller than the sum of its proper divisors (30345553005800).

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

21222221222200 is a wasteful number, since it uses less digits than its factorization.

21222221222200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13706 (or 13697 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 22.

Adding to 21222221222200 its reverse (222212222212), we get a palindrome (21444433444412).

It can be divided in two parts, 212222 and 21222200, that multiplied together give a square (4503817728400 = 2122220²).

The spelling of 21222221222200 in words is "twenty-one trillion, two hundred twenty-two billion, two hundred twenty-one million, two hundred twenty-two thousand, two hundred".