289780 has 12 divisors (see below), whose sum is σ = 608580. Its totient is φ = 115904.

The previous prime is 289771. The next prime is 289789. The reversal of 289780 is 87982.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (289771) and next prime (289789).

It can be written as a sum of positive squares in 2 ways, for example, as 70756 + 219024 = 266^2 + 468^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (289789) by changing a digit.

289780 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 in 3 ways as a sum of consecutive naturals, for example, 7225 + ... + 7264.

It is an arithmetic number, because the mean of its divisors is an integer number (50715).

2²⁸⁹⁷⁸⁰ is an apocalyptic number.

289780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

289780 is an abundant number, since it is smaller than the sum of its proper divisors (318800).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

289780 is a wasteful number, since it uses less digits than its factorization.

289780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14498 (or 14496 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 34.

The square root of 289780 is about 538.3121770869. The cubic root of 289780 is about 66.1743172768.

The spelling of 289780 in words is "two hundred eighty-nine thousand, seven hundred eighty".