20321120220 has 96 divisors (see below), whose sum is σ = 58284914688. Its totient is φ = 5287683072.

The previous prime is 20321120219. The next prime is 20321120227. The reversal of 20321120220 is 2202112302.

It is a happy number.

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 20321120220.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20321120227) 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 31 ways as a sum of consecutive naturals, for example, 939649 + ... + 961031.

It is an arithmetic number, because the mean of its divisors is an integer number (607134528).

Almost surely, 2^20321120220 is an apocalyptic number.

20321120220 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 20321120220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29142457344).

20321120220 is an abundant number, since it is smaller than the sum of its proper divisors (37963794468).

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

20321120220 is a wasteful number, since it uses less digits than its factorization.

20321120220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21779 (or 21777 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

Adding to 20321120220 its reverse (2202112302), we get a palindrome (22523232522).

The spelling of 20321120220 in words is "twenty billion, three hundred twenty-one million, one hundred twenty thousand, two hundred twenty".