688706 has 4 divisors (see below), whose sum is σ = 1033062. Its totient is φ = 344352.

The previous prime is 688697. The next prime is 688717. The reversal of 688706 is 607886.

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

It can be written as a sum of positive squares in only one way, i.e., 654481 + 34225 = 809^2 + 185^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 172175 + ... + 172178.

2⁶⁸⁸⁷⁰⁶ is an apocalyptic number.

688706 is a deficient number, since it is larger than the sum of its proper divisors (344356).

688706 is a wasteful number, since it uses less digits than its factorization.

688706 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 344355.

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 688706 is about 829.8831243012. The cubic root of 688706 is about 88.3102855102.

The spelling of 688706 in words is "six hundred eighty-eight thousand, seven hundred six".