688172 has 12 divisors (see below), whose sum is σ = 1232616. Its totient is φ = 336000.

The previous prime is 688159. The next prime is 688187. The reversal of 688172 is 271886.

It is an unprimeable number.

688172 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1829 + ... + 2172.

It is an arithmetic number, because the mean of its divisors is an integer number (102718).

2⁶⁸⁸¹⁷² is an apocalyptic number.

It is an amenable number.

688172 is a deficient number, since it is larger than the sum of its proper divisors (544444).

688172 is a wasteful number, since it uses less digits than its factorization.

688172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4048 (or 4046 counting only the distinct ones).

The product of its digits is 5376, while the sum is 32.

The square root of 688172 is about 829.5613298605. The cubic root of 688172 is about 88.2874553108.

It can be divided in two parts, 688 and 172, that multiplied together give a square (118336 = 344²).

The spelling of 688172 in words is "six hundred eighty-eight thousand, one hundred seventy-two".