2021222121221 has 8 divisors (see below), whose sum is σ = 2029884593088. Its totient is φ = 2012561928000.

The previous prime is 2021222121173. The next prime is 2021222121223. The reversal of 2021222121221 is 1221212221202.

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-2021222121221 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2021222121193 and 2021222121202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2021222121223) 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, 1220216 + ... + 2351886.

It is an arithmetic number, because the mean of its divisors is an integer number (253735574136).

Almost surely, 2^{2021222121221} is an apocalyptic number.

It is an amenable number.

2021222121221 is a deficient number, since it is larger than the sum of its proper divisors (8662471867).

2021222121221 is a wasteful number, since it uses less digits than its factorization.

2021222121221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1139323.

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 2021222121221 its reverse (1221212221202), we get a palindrome (3242434342423).

The spelling of 2021222121221 in words is "two trillion, twenty-one billion, two hundred twenty-two million, one hundred twenty-one thousand, two hundred twenty-one".