22012100221 has 4 divisors (see below), whose sum is σ = 22027505500. Its totient is φ = 21996694944.

The previous prime is 22012100207. The next prime is 22012100239. The reversal of 22012100221 is 12200121022.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12200121022 = 2 ⋅6100060511.

It can be written as a sum of positive squares in 2 ways, for example, as 4821219225 + 17190880996 = 69435^2 + 131114^2 .

It is a cyclic number.

It is not a de Polignac number, because 22012100221 - 2¹⁹ = 22011575933 is a prime.

It is a super-2 number, since 2×22012100221² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22012140221) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7700496 + ... + 7703353.

It is an arithmetic number, because the mean of its divisors is an integer number (5506876375).

Almost surely, 2^22012100221 is an apocalyptic number.

It is an amenable number.

22012100221 is a deficient number, since it is larger than the sum of its proper divisors (15405279).

22012100221 is a wasteful number, since it uses less digits than its factorization.

22012100221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15405278.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 22012100221 its reverse (12200121022), we get a palindrome (34212221243).

The spelling of 22012100221 in words is "twenty-two billion, twelve million, one hundred thousand, two hundred twenty-one".