686398 has 4 divisors (see below), whose sum is σ = 1029600. Its totient is φ = 343198.

The previous prime is 686363. The next prime is 686417. The reversal of 686398 is 893686.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×686398² = 942284428808, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 686398.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 171598 + ... + 171601.

It is an arithmetic number, because the mean of its divisors is an integer number (257400).

2⁶⁸⁶³⁹⁸ is an apocalyptic number.

686398 is a deficient number, since it is larger than the sum of its proper divisors (343202).

686398 is a wasteful number, since it uses less digits than its factorization.

686398 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 343201.

The product of its digits is 62208, while the sum is 40.

The square root of 686398 is about 828.4914000761. The cubic root of 686398 is about 88.2115262693.

The spelling of 686398 in words is "six hundred eighty-six thousand, three hundred ninety-eight".