221221101022100 has 144 divisors (see below), whose sum is σ = 496094004618240. Its totient is φ = 85537459814400.

The previous prime is 221221101022099. The next prime is 221221101022123. The reversal of 221221101022100 is 1220101122122.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 22728968834 + ... + 22728978566.

Almost surely, 2^{221221101022100} is an apocalyptic number.

221221101022100 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 221221101022100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (248047002309120).

221221101022100 is an abundant number, since it is smaller than the sum of its proper divisors (274872903596140).

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

221221101022100 is a wasteful number, since it uses less digits than its factorization.

221221101022100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17290 (or 17283 counting only the distinct ones).

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

Adding to 221221101022100 its reverse (1220101122122), we get a palindrome (222441202144222).

The spelling of 221221101022100 in words is "two hundred twenty-one trillion, two hundred twenty-one billion, one hundred one million, twenty-two thousand, one hundred".