689643 has 24 divisors (see below), whose sum is σ = 1086800. Its totient is φ = 419904.

The previous prime is 689641. The next prime is 689693. The reversal of 689643 is 346986.

689643 is a `hidden beast` number, since 6 + 8 + 9 + 643 = 666.

689643 is digitally balanced in base 7, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 689643 - 2¹ = 689641 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

689643 is strictly pandigital in base 7.

It is a junction number, because it is equal to n+sod(n) for n = 689598 and 689607.

It is not an unprimeable number, because it can be changed into a prime (689641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6273 + ... + 6381.

2⁶⁸⁹⁶⁴³ is an apocalyptic number.

689643 is a deficient number, since it is larger than the sum of its proper divisors (397157).

689643 is a wasteful number, since it uses less digits than its factorization.

689643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171 (or 168 counting only the distinct ones).

The product of its digits is 31104, while the sum is 36.

The square root of 689643 is about 830.4474697415. The cubic root of 689643 is about 88.3503167376.

The spelling of 689643 in words is "six hundred eighty-nine thousand, six hundred forty-three".