439123681 has 4 divisors (see below), whose sum is σ = 439219732. Its totient is φ = 439027632.

The previous prime is 439123667. The next prime is 439123691. The reversal of 439123681 is 186321934.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 149817600 + 289306081 = 12240^2 + 17009^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-439123681 is a prime.

It is a super-2 number, since 2×439123681² = 385659214429979522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 439123681.

It is not an unprimeable number, because it can be changed into a prime (439123621) 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, 40806 + ... + 50431.

It is an arithmetic number, because the mean of its divisors is an integer number (109804933).

Almost surely, 2^439123681 is an apocalyptic number.

It is an amenable number.

439123681 is a deficient number, since it is larger than the sum of its proper divisors (96051).

439123681 is an equidigital number, since it uses as much as digits as its factorization.

439123681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96050.

The product of its digits is 31104, while the sum is 37.

The square root of 439123681 is about 20955.2781179349. The cubic root of 439123681 is about 760.0852172450.

The spelling of 439123681 in words is "four hundred thirty-nine million, one hundred twenty-three thousand, six hundred eighty-one".