161686 has 8 divisors (see below), whose sum is σ = 277200. Its totient is φ = 69288.

The previous prime is 161683. The next prime is 161717. The reversal of 161686 is 686161.

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

It is a super-2 number, since 2×161686² = 52284725192, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161683) by changing a digit.

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, 5761 + ... + 5788.

It is an arithmetic number, because the mean of its divisors is an integer number (34650).

2¹⁶¹⁶⁸⁶ is an apocalyptic number.

161686 is a deficient number, since it is larger than the sum of its proper divisors (115514).

161686 is a wasteful number, since it uses less digits than its factorization.

161686 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11558.

The product of its digits is 1728, while the sum is 28.

The square root of 161686 is about 402.1019771153. The cubic root of 161686 is about 54.4783742722.

The spelling of 161686 in words is "one hundred sixty-one thousand, six hundred eighty-six".