2218968221 has 2 divisors, whose sum is σ = 2218968222. Its totient is φ = 2218968220.

The previous prime is 2218968161. The next prime is 2218968223. The reversal of 2218968221 is 1228698122.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2139062500 + 79905721 = 46250^2 + 8939^2 .

It is a cyclic number.

It is not a de Polignac number, because 2218968221 - 2¹⁴ = 2218951837 is a prime.

Together with 2218968223, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2218968223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1109484110 + 1109484111.

It is an arithmetic number, because the mean of its divisors is an integer number (1109484111).

Almost surely, 2^2218968221 is an apocalyptic number.

It is an amenable number.

2218968221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2218968221 is an equidigital number, since it uses as much as digits as its factorization.

2218968221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 55296, while the sum is 41.

The square root of 2218968221 is about 47105.9255402120. The cubic root of 2218968221 is about 1304.3186200370.

The spelling of 2218968221 in words is "two billion, two hundred eighteen million, nine hundred sixty-eight thousand, two hundred twenty-one".