2181172211 has 2 divisors, whose sum is σ = 2181172212. Its totient is φ = 2181172210.

The previous prime is 2181172151. The next prime is 2181172247. The reversal of 2181172211 is 1122711812.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2181172211 - 2¹⁴ = 2181155827 is a prime.

It is not a weakly prime, because it can be changed into another prime (2181172261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1090586105 + 1090586106.

It is an arithmetic number, because the mean of its divisors is an integer number (1090586106).

Almost surely, 2^2181172211 is an apocalyptic number.

2181172211 is a deficient number, since it is larger than the sum of its proper divisors (1).

2181172211 is an equidigital number, since it uses as much as digits as its factorization.

2181172211 is an evil number, because the sum of its binary digits is even.

The product of its digits is 448, while the sum is 26.

The square root of 2181172211 is about 46703.0214333077. The cubic root of 2181172211 is about 1296.8706210844.

The spelling of 2181172211 in words is "two billion, one hundred eighty-one million, one hundred seventy-two thousand, two hundred eleven".