161985 has 8 divisors (see below), whose sum is σ = 259200. Its totient is φ = 86384.

The previous prime is 161983. The next prime is 161999. The reversal of 161985 is 589161.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 161985 - 2¹ = 161983 is a prime.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 161985.

It is not an unprimeable number, because it can be changed into a prime (161983) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5385 + ... + 5414.

It is an arithmetic number, because the mean of its divisors is an integer number (32400).

2¹⁶¹⁹⁸⁵ is an apocalyptic number.

161985 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

161985 is a deficient number, since it is larger than the sum of its proper divisors (97215).

161985 is a wasteful number, since it uses less digits than its factorization.

161985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10807.

The product of its digits is 2160, while the sum is 30.

The square root of 161985 is about 402.4736016188. The cubic root of 161985 is about 54.5119352140.

The spelling of 161985 in words is "one hundred sixty-one thousand, nine hundred eighty-five".