20021220202221 has 24 divisors (see below), whose sum is σ = 33088164729984. Its totient is φ = 11427799033440.

The previous prime is 20021220202219. The next prime is 20021220202229. The reversal of 20021220202221 is 12220202212002.

20021220202221 is a `hidden beast` number, since 2 + 0 + 0 + 21 + 220 + 202 + 221 = 666.

It is not a de Polignac number, because 20021220202221 - 2¹ = 20021220202219 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20021220202194 and 20021220202203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20021220202229) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 179085690 + ... + 179197451.

It is an arithmetic number, because the mean of its divisors is an integer number (1378673530416).

Almost surely, 2^{20021220202221} is an apocalyptic number.

20021220202221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20021220202221 is a deficient number, since it is larger than the sum of its proper divisors (13066944527763).

20021220202221 is a wasteful number, since it uses less digits than its factorization.

20021220202221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 358284041 (or 358284038 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

Adding to 20021220202221 its reverse (12220202212002), we get a palindrome (32241422414223).

The spelling of 20021220202221 in words is "twenty trillion, twenty-one billion, two hundred twenty million, two hundred two thousand, two hundred twenty-one".