11217989 has 2 divisors, whose sum is σ = 11217990. Its totient is φ = 11217988.

The previous prime is 11217959. The next prime is 11217991. The reversal of 11217989 is 98971211.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10029889 + 1188100 = 3167^2 + 1090^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11217989 is a prime.

Together with 11217991, 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 (11217949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5608994 + 5608995.

It is an arithmetic number, because the mean of its divisors is an integer number (5608995).

Almost surely, 2^11217989 is an apocalyptic number.

It is an amenable number.

11217989 is a deficient number, since it is larger than the sum of its proper divisors (1).

11217989 is an equidigital number, since it uses as much as digits as its factorization.

11217989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9072, while the sum is 38.

The square root of 11217989 is about 3349.3266487460. The cubic root of 11217989 is about 223.8575106235.

The spelling of 11217989 in words is "eleven million, two hundred seventeen thousand, nine hundred eighty-nine".