688228 has 24 divisors (see below), whose sum is σ = 1323000. Its totient is φ = 311808.

The previous prime is 688223. The next prime is 688249. The reversal of 688228 is 822886.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 268324 + 419904 = 518^2 + 648^2 .

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a d-powerful number, because it can be written as 6² + 8² + 2¹⁷ + 8⁵ + 2¹⁸ + 8⁶ .

It is a junction number, because it is equal to n+sod(n) for n = 688193 and 688202.

It is not an unprimeable number, because it can be changed into a prime (688223) by changing a digit.

688228 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 7 ways as a sum of consecutive naturals, for example, 1798 + ... + 2146.

It is an arithmetic number, because the mean of its divisors is an integer number (55125).

2⁶⁸⁸²²⁸ is an apocalyptic number.

688228 is a gapful number since it is divisible by the number (68) formed by its first and last digit.

It is an amenable number.

688228 is a deficient number, since it is larger than the sum of its proper divisors (634772).

688228 is a wasteful number, since it uses less digits than its factorization.

688228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 399 (or 397 counting only the distinct ones).

The product of its digits is 12288, while the sum is 34.

The square root of 688228 is about 829.5950819526. The cubic root of 688228 is about 88.2898500432.

It can be divided in two parts, 68 and 8228, that multiplied together give a square (559504 = 748²).

The spelling of 688228 in words is "six hundred eighty-eight thousand, two hundred twenty-eight".