689680 has 40 divisors (see below), whose sum is σ = 1653912. Its totient is φ = 267264.

The previous prime is 689641. The next prime is 689693. The reversal of 689680 is 86986.

It can be written as a sum of positive squares in 4 ways, for example, as 99856 + 589824 = 316^2 + 768^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (37).

It is an Ulam number.

It is a nialpdrome in base 16.

It is an unprimeable number.

689680 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, 2844 + ... + 3076.

2⁶⁸⁹⁶⁸⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 689680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (826956).

689680 is an abundant number, since it is smaller than the sum of its proper divisors (964232).

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

689680 is a wasteful number, since it uses less digits than its factorization.

689680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 283 (or 277 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 689680 is about 830.4697465892. The cubic root of 689680 is about 88.3518967354.

It can be divided in two parts, 689 and 680, that added together give a square (1369 = 37²).

The spelling of 689680 in words is "six hundred eighty-nine thousand, six hundred eighty".