201220122100 has 72 divisors (see below), whose sum is σ = 451961072640. Its totient is φ = 77668456320.

The previous prime is 201220122097. The next prime is 201220122109. The reversal of 201220122100 is 1221022102.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201220122109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5337517 + ... + 5375083.

It is an arithmetic number, because the mean of its divisors is an integer number (6277237120).

Almost surely, 2^201220122100 is an apocalyptic number.

201220122100 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 201220122100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (225980536320).

201220122100 is an abundant number, since it is smaller than the sum of its proper divisors (250740950540).

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

201220122100 is a wasteful number, since it uses less digits than its factorization.

201220122100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39457 (or 39450 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 201220122100 its reverse (1221022102), we get a palindrome (202441144202).

The spelling of 201220122100 in words is "two hundred one billion, two hundred twenty million, one hundred twenty-two thousand, one hundred".