287321 has 2 divisors, whose sum is σ = 287322.
Its totient is φ = 287320.
The previous prime is 287297. The next prime is 287327. The reversal of 287321 is 123782.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 287296 + 25 = 536^2 + 5^2
It is a cyclic number.
It is not a de Polignac number, because 287321 - 26 = 287257 is a prime.
It is a Sophie Germain prime.
It is a Chen prime.
It is an Ulam number.
It is a Curzon number.
It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 287321.
It is not a weakly prime, because it can be changed into another prime (287327) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 143660 + 143661.
It is an arithmetic number, because the mean of its divisors is an integer number (143661).
2287321 is an apocalyptic number.
It is an amenable number.
287321 is a deficient number, since it is larger than the sum of its proper divisors (1).
287321 is an equidigital number, since it uses as much as digits as its factorization.
287321 is an evil number, because the sum of its binary digits is even.
The product of its digits is 672, while the sum is 23.
The square root of 287321 is about 536.0233203882.
The cubic root of 287321 is about 65.9866057913.
The spelling of 287321 in words is "two hundred eighty-seven thousand, three hundred twenty-one".