129985 has 4 divisors (see below), whose sum is σ = 155988. Its totient is φ = 103984.

The previous prime is 129971. The next prime is 130003. The reversal of 129985 is 589921.

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 28224 + 101761 = 168^2 + 319^2 .

It is a cyclic number.

It is not a de Polignac number, because 129985 - 2⁵ = 129953 is a prime.

It is a super-2 number, since 2×129985² = 33792200450, which contains 22 as substring.

It is an Ulam number.

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 129985.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12994 + ... + 13003.

It is an arithmetic number, because the mean of its divisors is an integer number (38997).

2¹²⁹⁹⁸⁵ is an apocalyptic number.

It is an amenable number.

129985 is a deficient number, since it is larger than the sum of its proper divisors (26003).

129985 is an equidigital number, since it uses as much as digits as its factorization.

129985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26002.

The product of its digits is 6480, while the sum is 34.

The square root of 129985 is about 360.5343256890. The cubic root of 129985 is about 50.6560217326.

The spelling of 129985 in words is "one hundred twenty-nine thousand, nine hundred eighty-five".