211838197 has 2 divisors, whose sum is σ = 211838198. Its totient is φ = 211838196.

The previous prime is 211838171. The next prime is 211838219. The reversal of 211838197 is 791838112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 207619281 + 4218916 = 14409^2 + 2054^2 .

It is a cyclic number.

It is not a de Polignac number, because 211838197 - 2¹⁹ = 211313909 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211838117) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105919098 + 105919099.

It is an arithmetic number, because the mean of its divisors is an integer number (105919099).

Almost surely, 2^211838197 is an apocalyptic number.

It is an amenable number.

211838197 is a deficient number, since it is larger than the sum of its proper divisors (1).

211838197 is an equidigital number, since it uses as much as digits as its factorization.

211838197 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24192, while the sum is 40.

The square root of 211838197 is about 14554.6623801447. The cubic root of 211838197 is about 596.1214609517.

The spelling of 211838197 in words is "two hundred eleven million, eight hundred thirty-eight thousand, one hundred ninety-seven".