688220 has 24 divisors (see below), whose sum is σ = 1557024. Its totient is φ = 254016.

The previous prime is 688217. The next prime is 688223. The reversal of 688220 is 22886.

It is an interprime number because it is at equal distance from previous prime (688217) and next prime (688223).

It is a Harshad number since it is a multiple of its sum of digits (26).

It is a self number, because there is not a number n which added to its sum of digits gives 688220.

It is a congruent number.

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

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1064 + ... + 1583.

It is an arithmetic number, because the mean of its divisors is an integer number (64876).

2⁶⁸⁸²²⁰ is an apocalyptic number.

It is an amenable number.

688220 is an abundant number, since it is smaller than the sum of its proper divisors (868804).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

688220 is a wasteful number, since it uses less digits than its factorization.

688220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2669 (or 2667 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 26.

The square root of 688220 is about 829.5902603093. The cubic root of 688220 is about 88.2895079465.

The spelling of 688220 in words is "six hundred eighty-eight thousand, two hundred twenty".