489 has 4 divisors (see below), whose sum is σ = 656. Its totient is φ = 324.

The previous prime is 487. The next prime is 491. The reversal of 489 is 984.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (487) and next prime (491).

It is not a de Polignac number, because 489 - 2^{1} = 487 is a prime.

It is a D-number.

It is a Duffinian number.

489 is a lucky number.

It is a plaindrome in base 7, base 10, base 12, base 14 and base 15.

It is a nialpdrome in base 8.

It is not an unprimeable number, because it can be changed into a prime (487) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 79 + ... + 84.

It is an arithmetic number, because the mean of its divisors is an integer number (164).

It is an amenable number.

489 is a deficient number, since it is larger than the sum of its proper divisors (167).

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

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

The sum of its prime factors is 166.

The product of its digits is 288, while the sum is 21.

The square root of 489 is about 22.1133443875. The cubic root of 489 is about 7.8783684255.

Adding to 489 its product of digits (288), we get a palindrome (777).

The spelling of 489 in words is "four hundred eighty-nine", and thus it is an aban number.

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