221222122100 has 72 divisors (see below), whose sum is σ = 549356922240. Its totient is φ = 75747208320.

The previous prime is 221222122091. The next prime is 221222122129. The reversal of 221222122100 is 1221222122.

It is a happy number.

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, 321161 + ... + 738639.

Almost surely, 2^221222122100 is an apocalyptic number.

221222122100 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 221222122100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (274678461120).

221222122100 is an abundant number, since it is smaller than the sum of its proper divisors (328134800140).

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

221222122100 is a wasteful number, since it uses less digits than its factorization.

221222122100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 418257 (or 418250 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 221222122100 its reverse (1221222122), we get a palindrome (222443344222).

The spelling of 221222122100 in words is "two hundred twenty-one billion, two hundred twenty-two million, one hundred twenty-two thousand, one hundred".