687199 has 4 divisors (see below), whose sum is σ = 689040. Its totient is φ = 685360.

The previous prime is 687179. The next prime is 687223. The reversal of 687199 is 991786.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 991786 = 2 ⋅495893.

It is a cyclic number.

It is not a de Polignac number, because 687199 - 2⁹ = 686687 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (687109) 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, 139 + ... + 1180.

It is an arithmetic number, because the mean of its divisors is an integer number (172260).

2⁶⁸⁷¹⁹⁹ is an apocalyptic number.

687199 is a deficient number, since it is larger than the sum of its proper divisors (1841).

687199 is a wasteful number, since it uses less digits than its factorization.

687199 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1840.

The product of its digits is 27216, while the sum is 40.

The square root of 687199 is about 828.9746678880. The cubic root of 687199 is about 88.2458260805.

The spelling of 687199 in words is "six hundred eighty-seven thousand, one hundred ninety-nine".