20202021220121 has 8 divisors (see below), whose sum is σ = 22286657556744. Its totient is φ = 18193189841280.

The previous prime is 20202021220099. The next prime is 20202021220133. The reversal of 20202021220121 is 12102212020202.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 2236927044496 + 17965094175625 = 1495636^2 + 4238525^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 20202021220121 - 2¹⁴ = 20202021203737 is a prime.

It is a super-2 number, since 2×20202021220121² (a number of 27 digits) contains 22 as substring.

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 20202021220121.

It is not an unprimeable number, because it can be changed into a prime (20202021222121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18951238886 + ... + 18951239951.

It is an arithmetic number, because the mean of its divisors is an integer number (2785832194593).

Almost surely, 2^{20202021220121} is an apocalyptic number.

It is an amenable number.

20202021220121 is a deficient number, since it is larger than the sum of its proper divisors (2084636336623).

20202021220121 is a wasteful number, since it uses less digits than its factorization.

20202021220121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37902478891.

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

Adding to 20202021220121 its reverse (12102212020202), we get a palindrome (32304233240323).

The spelling of 20202021220121 in words is "twenty trillion, two hundred two billion, twenty-one million, two hundred twenty thousand, one hundred twenty-one".