21202121002220 has 48 divisors (see below), whose sum is σ = 47297826760800. Its totient is φ = 7960777044480.

The previous prime is 21202121002193. The next prime is 21202121002291. The reversal of 21202121002220 is 2220012120212.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 255899201 + ... + 255982040.

It is an arithmetic number, because the mean of its divisors is an integer number (985371390850).

Almost surely, 2^{21202121002220} is an apocalyptic number.

21202121002220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21202121002220 is an abundant number, since it is smaller than the sum of its proper divisors (26095705758580).

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

21202121002220 is a wasteful number, since it uses less digits than its factorization.

21202121002220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 511881378 (or 511881376 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 21202121002220 its reverse (2220012120212), we get a palindrome (23422133122432).

The spelling of 21202121002220 in words is "twenty-one trillion, two hundred two billion, one hundred twenty-one million, two thousand, two hundred twenty".