2775212221 has 2 divisors, whose sum is σ = 2775212222. Its totient is φ = 2775212220.

The previous prime is 2775212203. The next prime is 2775212233. The reversal of 2775212221 is 1222125772.

2775212221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1433455321 + 1341756900 = 37861^2 + 36630^2 .

It is a cyclic number.

It is not a de Polignac number, because 2775212221 - 2¹⁵ = 2775179453 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2775212201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1387606110 + 1387606111.

It is an arithmetic number, because the mean of its divisors is an integer number (1387606111).

Almost surely, 2^2775212221 is an apocalyptic number.

It is an amenable number.

2775212221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2775212221 is an equidigital number, since it uses as much as digits as its factorization.

2775212221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7840, while the sum is 31.

The square root of 2775212221 is about 52680.2830383437. The cubic root of 2775212221 is about 1405.2882006526.

Adding to 2775212221 its reverse (1222125772), we get a palindrome (3997337993).

The spelling of 2775212221 in words is "two billion, seven hundred seventy-five million, two hundred twelve thousand, two hundred twenty-one".