688005 has 12 divisors (see below), whose sum is σ = 1192620. Its totient is φ = 366912.

The previous prime is 688003. The next prime is 688013. The reversal of 688005 is 500886.

It can be written as a sum of positive squares in 2 ways, for example, as 338724 + 349281 = 582^2 + 591^2 .

It is not a de Polignac number, because 688005 - 2¹ = 688003 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 688005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688003) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7600 + ... + 7689.

It is an arithmetic number, because the mean of its divisors is an integer number (99385).

2⁶⁸⁸⁰⁰⁵ is an apocalyptic number.

It is an amenable number.

688005 is a deficient number, since it is larger than the sum of its proper divisors (504615).

688005 is a wasteful number, since it uses less digits than its factorization.

688005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15300 (or 15297 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 688005 is about 829.4606681453. The cubic root of 688005 is about 88.2803131052.

The spelling of 688005 in words is "six hundred eighty-eight thousand, five".