439987 has 4 divisors (see below), whose sum is σ = 446256. Its totient is φ = 433720.

The previous prime is 439981. The next prime is 439991. The reversal of 439987 is 789934.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 789934 = 2 ⋅394967.

It is a cyclic number.

It is not a de Polignac number, because 439987 - 2¹⁵ = 407219 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (439981) 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, 3028 + ... + 3169.

It is an arithmetic number, because the mean of its divisors is an integer number (111564).

2⁴³⁹⁹⁸⁷ is an apocalyptic number.

439987 is a deficient number, since it is larger than the sum of its proper divisors (6269).

439987 is an equidigital number, since it uses as much as digits as its factorization.

439987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6268.

The product of its digits is 54432, while the sum is 40.

The square root of 439987 is about 663.3151588800. The cubic root of 439987 is about 76.0583001415.

The spelling of 439987 in words is "four hundred thirty-nine thousand, nine hundred eighty-seven".