20002221202121 has 8 divisors (see below), whose sum is σ = 20005095518280. Its totient is φ = 19999347119488.

The previous prime is 20002221202109. The next prime is 20002221202129. The reversal of 20002221202121 is 12120212220002.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 1205140688521 + 18797080513600 = 1097789^2 + 4335560^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20002221202121 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20002221202121.

It is not an unprimeable number, because it can be changed into a prime (20002221202129) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 232354475 + ... + 232440543.

It is an arithmetic number, because the mean of its divisors is an integer number (2500636939785).

Almost surely, 2^{20002221202121} is an apocalyptic number.

It is an amenable number.

20002221202121 is a deficient number, since it is larger than the sum of its proper divisors (2874316159).

20002221202121 is a wasteful number, since it uses less digits than its factorization.

20002221202121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116763.

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

Adding to 20002221202121 its reverse (12120212220002), we get a palindrome (32122433422123).

The spelling of 20002221202121 in words is "twenty trillion, two billion, two hundred twenty-one million, two hundred two thousand, one hundred twenty-one".