201221021122100 has 144 divisors (see below), whose sum is σ = 500197519476480. Its totient is φ = 68828480179200.

The previous prime is 201221021122091. The next prime is 201221021122123. The reversal of 201221021122100 is 1221120122102.

It is a super-2 number, since 2×201221021122100² (a number of 29 digits) contains 22 as substring.

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, 1202952470 + ... + 1203119730.

Almost surely, 2^{201221021122100} is an apocalyptic number.

201221021122100 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 201221021122100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (250098759738240).

201221021122100 is an abundant number, since it is smaller than the sum of its proper divisors (298976498354380).

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

201221021122100 is a wasteful number, since it uses less digits than its factorization.

201221021122100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171298 (or 171291 counting only the distinct ones).

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

Adding to 201221021122100 its reverse (1221120122102), we get a palindrome (202442141244202).

The spelling of 201221021122100 in words is "two hundred one trillion, two hundred twenty-one billion, twenty-one million, one hundred twenty-two thousand, one hundred".