686957 has 4 divisors (see below), whose sum is σ = 688896. Its totient is φ = 685020.

The previous prime is 686947. The next prime is 686963. The reversal of 686957 is 759686.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 686957 - 2⁶ = 686893 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 15.

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 686957.

It is not an unprimeable number, because it can be changed into a prime (686947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 269 + ... + 1202.

It is an arithmetic number, because the mean of its divisors is an integer number (172224).

2⁶⁸⁶⁹⁵⁷ is an apocalyptic number.

It is an amenable number.

686957 is a deficient number, since it is larger than the sum of its proper divisors (1939).

686957 is a wasteful number, since it uses less digits than its factorization.

686957 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1938.

The product of its digits is 90720, while the sum is 41.

The square root of 686957 is about 828.8286915883. The cubic root of 686957 is about 88.2354661522.

The spelling of 686957 in words is "six hundred eighty-six thousand, nine hundred fifty-seven".