689778 has 12 divisors (see below), whose sum is σ = 1494558. Its totient is φ = 229920.

The previous prime is 689771. The next prime is 689779. The reversal of 689778 is 877986.

It can be written as a sum of positive squares in only one way, i.e., 558009 + 131769 = 747^2 + 363^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (689771) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 19143 + ... + 19178.

2⁶⁸⁹⁷⁷⁸ is an apocalyptic number.

689778 is an abundant number, since it is smaller than the sum of its proper divisors (804780).

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

689778 is a wasteful number, since it uses less digits than its factorization.

689778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38329 (or 38326 counting only the distinct ones).

The product of its digits is 169344, while the sum is 45.

The square root of 689778 is about 830.5287472448. The cubic root of 689778 is about 88.3560813214.

The spelling of 689778 in words is "six hundred eighty-nine thousand, seven hundred seventy-eight".