21122021022221 has 16 divisors (see below), whose sum is σ = 26096705516160. Its totient is φ = 16688156414400.

The previous prime is 21122021022211. The next prime is 21122021022227. The reversal of 21122021022221 is 12222012022112.

It is a cyclic number.

It is not a de Polignac number, because 21122021022221 - 2²² = 21122016827917 is a prime.

It is a super-2 number, since 2×21122021022221² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21122021022193 and 21122021022202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21122021022227) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2146105730 + ... + 2146115571.

It is an arithmetic number, because the mean of its divisors is an integer number (1631044094760).

Almost surely, 2^{21122021022221} is an apocalyptic number.

It is an amenable number.

21122021022221 is a deficient number, since it is larger than the sum of its proper divisors (4974684493939).

21122021022221 is a wasteful number, since it uses less digits than its factorization.

21122021022221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4292221364.

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

Adding to 21122021022221 its reverse (12222012022112), we get a palindrome (33344033044333).

The spelling of 21122021022221 in words is "twenty-one trillion, one hundred twenty-two billion, twenty-one million, twenty-two thousand, two hundred twenty-one".