688745 has 8 divisors (see below), whose sum is σ = 833280. Its totient is φ = 546480.

The previous prime is 688741. The next prime is 688747. The reversal of 688745 is 547886.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 688745 - 2² = 688741 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 688699 and 688708.

It is not an unprimeable number, because it can be changed into a prime (688741) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 200 + ... + 1190.

It is an arithmetic number, because the mean of its divisors is an integer number (104160).

2⁶⁸⁸⁷⁴⁵ is an apocalyptic number.

It is an amenable number.

688745 is a deficient number, since it is larger than the sum of its proper divisors (144535).

688745 is a wasteful number, since it uses less digits than its factorization.

688745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1135.

The product of its digits is 53760, while the sum is 38.

The square root of 688745 is about 829.9066212533. The cubic root of 688745 is about 88.3119524218.

The spelling of 688745 in words is "six hundred eighty-eight thousand, seven hundred forty-five".