21201100122120 has 32 divisors (see below), whose sum is σ = 63603300366720. Its totient is φ = 5653626699200.

The previous prime is 21201100122073. The next prime is 21201100122157. The reversal of 21201100122120 is 2122100110212.

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 21201100122120.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 88337917056 + ... + 88337917295.

It is an arithmetic number, because the mean of its divisors is an integer number (1987603136460).

Almost surely, 2^{21201100122120} is an apocalyptic number.

21201100122120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21201100122120 is an abundant number, since it is smaller than the sum of its proper divisors (42402200244600).

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

21201100122120 is a wasteful number, since it uses less digits than its factorization.

21201100122120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 176675834365 (or 176675834361 counting only the distinct ones).

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

Adding to 21201100122120 its reverse (2122100110212), we get a palindrome (23323200232332).

The spelling of 21201100122120 in words is "twenty-one trillion, two hundred one billion, one hundred million, one hundred twenty-two thousand, one hundred twenty".