289987 has 2 divisors, whose sum is σ = 289988. Its totient is φ = 289986.

The previous prime is 289973. The next prime is 289999. The reversal of 289987 is 789982.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 289987 - 2⁷ = 289859 is a prime.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 289987.

It is not a weakly prime, because it can be changed into another prime (289937) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 144993 + 144994.

It is an arithmetic number, because the mean of its divisors is an integer number (144994).

2²⁸⁹⁹⁸⁷ is an apocalyptic number.

289987 is a deficient number, since it is larger than the sum of its proper divisors (1).

289987 is an equidigital number, since it uses as much as digits as its factorization.

289987 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 72576, while the sum is 43.

The square root of 289987 is about 538.5044103812. The cubic root of 289987 is about 66.1900704037.

The spelling of 289987 in words is "two hundred eighty-nine thousand, nine hundred eighty-seven".