689138 has 6 divisors (see below), whose sum is σ = 1035471. Its totient is φ = 343982.

The previous prime is 689131. The next prime is 689141. The reversal of 689138 is 831986.

689138 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 344569 + 344569 = 587^2 + 587^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=587.

It is a super-2 number, since 2×689138² = 949822366088, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 689098 and 689107.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 689138.

It is not an unprimeable number, because it can be changed into a prime (689131) by changing a digit.

689138 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 2 ways as a sum of consecutive naturals, for example, 881 + ... + 1467.

2⁶⁸⁹¹³⁸ is an apocalyptic number.

689138 is a deficient number, since it is larger than the sum of its proper divisors (346333).

689138 is an frugal number, since it uses more digits than its factorization.

689138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1176 (or 589 counting only the distinct ones).

The product of its digits is 10368, while the sum is 35.

The square root of 689138 is about 830.1433611130. The cubic root of 689138 is about 88.3287462513.

Multiplying 689138 by its product of digits (10368), we get a square (7144982784 = 84528²).

It can be divided in two parts, 68913 and 8, that added together give a cube (68921 = 41³).

The spelling of 689138 in words is "six hundred eighty-nine thousand, one hundred thirty-eight".