201221121200100 has 72 divisors (see below), whose sum is σ = 585452290217760. Its totient is φ = 53359194881280.

The previous prime is 201221121200087. The next prime is 201221121200107. The reversal of 201221121200100 is 1002121122102.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 201221121200100.

It is not an unprimeable number, because it can be changed into a prime (201221121200107) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1873513537 + ... + 1873620936.

It is an arithmetic number, because the mean of its divisors is an integer number (8131281808580).

Almost surely, 2^{201221121200100} is an apocalyptic number.

201221121200100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

201221121200100 is an abundant number, since it is smaller than the sum of its proper divisors (384231169017660).

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

201221121200100 is a wasteful number, since it uses less digits than its factorization.

201221121200100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3747134669 (or 3747134662 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 201221121200100 its reverse (1002121122102), we get a palindrome (202223242322202).

The spelling of 201221121200100 in words is "two hundred one trillion, two hundred twenty-one billion, one hundred twenty-one million, two hundred thousand, one hundred".