202121001220 has 96 divisors (see below), whose sum is σ = 451474194528. Its totient is φ = 75745984512.

The previous prime is 202121001217. The next prime is 202121001221. The reversal of 202121001220 is 22100121202.

It is a happy number.

202121001220 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 16 ways, for example, as 93494069824 + 108626931396 = 305768^2 + 329586^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 202121001220.

It is not an unprimeable number, because it can be changed into a prime (202121001221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 95654884 + ... + 95656996.

It is an arithmetic number, because the mean of its divisors is an integer number (4702856193).

Almost surely, 2^202121001220 is an apocalyptic number.

202121001220 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 202121001220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (225737097264).

202121001220 is an abundant number, since it is smaller than the sum of its proper divisors (249353193308).

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

202121001220 is a wasteful number, since it uses less digits than its factorization.

202121001220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3289 (or 3287 counting only the distinct ones).

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

Adding to 202121001220 its reverse (22100121202), we get a palindrome (224221122422).

The spelling of 202121001220 in words is "two hundred two billion, one hundred twenty-one million, one thousand, two hundred twenty".