22131222221 has 2 divisors, whose sum is σ = 22131222222. Its totient is φ = 22131222220.

The previous prime is 22131222163. The next prime is 22131222229. The reversal of 22131222221 is 12222213122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18527020996 + 3604201225 = 136114^2 + 60035^2 .

It is a cyclic number.

It is not a de Polignac number, because 22131222221 - 2³⁰ = 21057480397 is a prime.

It is a super-3 number, since 3×22131222221³ (a number of 32 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 22131222193 and 22131222202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22131222229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11065611110 + 11065611111.

It is an arithmetic number, because the mean of its divisors is an integer number (11065611111).

Almost surely, 2^22131222221 is an apocalyptic number.

It is an amenable number.

22131222221 is a deficient number, since it is larger than the sum of its proper divisors (1).

22131222221 is an equidigital number, since it uses as much as digits as its factorization.

22131222221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 384, while the sum is 20.

Adding to 22131222221 its reverse (12222213122), we get a palindrome (34353435343).

Subtracting from 22131222221 its reverse (12222213122), we obtain a palindrome (9909009099).

The spelling of 22131222221 in words is "twenty-two billion, one hundred thirty-one million, two hundred twenty-two thousand, two hundred twenty-one".