987209 has 2 divisors, whose sum is σ = 987210. Its totient is φ = 987208.

The previous prime is 987199. The next prime is 987211. The reversal of 987209 is 902789.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 861184 + 126025 = 928^2 + 355^2 .

It is an emirp because it is prime and its reverse (902789) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 987209 - 2⁴ = 987193 is a prime.

Together with 987211, it forms a pair of twin primes.

It is a Chen prime.

It is a plaindrome in base 15.

It is not a weakly prime, because it can be changed into another prime (987299) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 493604 + 493605.

It is an arithmetic number, because the mean of its divisors is an integer number (493605).

2⁹⁸⁷²⁰⁹ is an apocalyptic number.

It is an amenable number.

987209 is a deficient number, since it is larger than the sum of its proper divisors (1).

987209 is an equidigital number, since it uses as much as digits as its factorization.

987209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9072, while the sum is 35.

The square root of 987209 is about 993.5839169391. The cubic root of 987209 is about 99.5718024187.

The spelling of 987209 in words is "nine hundred eighty-seven thousand, two hundred nine".