211897913 has 2 divisors, whose sum is σ = 211897914. Its totient is φ = 211897912.

The previous prime is 211897897. The next prime is 211897951. The reversal of 211897913 is 319798112.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 158432569 + 53465344 = 12587^2 + 7312^2 .

It is a cyclic number.

It is not a de Polignac number, because 211897913 - 2⁴ = 211897897 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (211897313) 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, 105948956 + 105948957.

It is an arithmetic number, because the mean of its divisors is an integer number (105948957).

Almost surely, 2^211897913 is an apocalyptic number.

It is an amenable number.

211897913 is a deficient number, since it is larger than the sum of its proper divisors (1).

211897913 is an equidigital number, since it uses as much as digits as its factorization.

211897913 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27216, while the sum is 41.

The square root of 211897913 is about 14556.7136744528. The cubic root of 211897913 is about 596.1774701217.

The spelling of 211897913 in words is "two hundred eleven million, eight hundred ninety-seven thousand, nine hundred thirteen".