689780 has 48 divisors (see below), whose sum is σ = 1787520. Its totient is φ = 217728.

The previous prime is 689779. The next prime is 689789. The reversal of 689780 is 87986.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (689789) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1631 + ... + 2009.

It is an arithmetic number, because the mean of its divisors is an integer number (37240).

2⁶⁸⁹⁷⁸⁰ 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 689780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (893760).

689780 is an abundant number, since it is smaller than the sum of its proper divisors (1097740).

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

689780 is a wasteful number, since it uses less digits than its factorization.

689780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 408 (or 406 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 38.

The square root of 689780 is about 830.5299512962. The cubic root of 689780 is about 88.3561667170.

The spelling of 689780 in words is "six hundred eighty-nine thousand, seven hundred eighty".