686146 has 4 divisors (see below), whose sum is σ = 1029222. Its totient is φ = 343072.

The previous prime is 686143. The next prime is 686149. The reversal of 686146 is 641686.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 641686 = 2 ⋅320843.

It is an interprime number because it is at equal distance from previous prime (686143) and next prime (686149).

It can be written as a sum of positive squares in only one way, i.e., 505521 + 180625 = 711^2 + 425^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (686141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 171535 + ... + 171538.

2⁶⁸⁶¹⁴⁶ is an apocalyptic number.

686146 is a deficient number, since it is larger than the sum of its proper divisors (343076).

686146 is a wasteful number, since it uses less digits than its factorization.

686146 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 343075.

The product of its digits is 6912, while the sum is 31.

The square root of 686146 is about 828.3393024600. The cubic root of 686146 is about 88.2007297996.

The spelling of 686146 in words is "six hundred eighty-six thousand, one hundred forty-six".