139985 has 4 divisors (see below), whose sum is σ = 167988. Its totient is φ = 111984.

The previous prime is 139981. The next prime is 139987. The reversal of 139985 is 589931.

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 96721 + 43264 = 311^2 + 208^2 .

It is a cyclic number.

It is not a de Polignac number, because 139985 - 2² = 139981 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 139985.

It is not an unprimeable number, because it can be changed into a prime (139981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13994 + ... + 14003.

It is an arithmetic number, because the mean of its divisors is an integer number (41997).

2¹³⁹⁹⁸⁵ is an apocalyptic number.

It is an amenable number.

139985 is a deficient number, since it is larger than the sum of its proper divisors (28003).

139985 is an equidigital number, since it uses as much as digits as its factorization.

139985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28002.

The product of its digits is 9720, while the sum is 35.

The square root of 139985 is about 374.1456935473. The cubic root of 139985 is about 51.9230864901.

The spelling of 139985 in words is "one hundred thirty-nine thousand, nine hundred eighty-five".