439681 has 4 divisors (see below), whose sum is σ = 479664. Its totient is φ = 399700.

The previous prime is 439667. The next prime is 439687. The reversal of 439681 is 186934.

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 a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-439681 is a prime.

It is a super-2 number, since 2×439681² = 386638763522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (439687) 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, 19975 + ... + 19996.

It is an arithmetic number, because the mean of its divisors is an integer number (119916).

2⁴³⁹⁶⁸¹ is an apocalyptic number.

It is an amenable number.

439681 is a deficient number, since it is larger than the sum of its proper divisors (39983).

439681 is a wasteful number, since it uses less digits than its factorization.

439681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39982.

The product of its digits is 5184, while the sum is 31.

The square root of 439681 is about 663.0844591755. The cubic root of 439681 is about 76.0406638345.

The spelling of 439681 in words is "four hundred thirty-nine thousand, six hundred eighty-one".