842689 has 4 divisors (see below), whose sum is σ = 844740. Its totient is φ = 840640.

The previous prime is 842657. The next prime is 842701. The reversal of 842689 is 986248.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 242064 + 600625 = 492^2 + 775^2 .

It is a cyclic number.

It is not a de Polignac number, because 842689 - 2⁵ = 842657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (842089) 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 3 ways as a sum of consecutive naturals, for example, 172 + ... + 1309.

It is an arithmetic number, because the mean of its divisors is an integer number (211185).

2⁸⁴²⁶⁸⁹ is an apocalyptic number.

It is an amenable number.

842689 is a deficient number, since it is larger than the sum of its proper divisors (2051).

842689 is a wasteful number, since it uses less digits than its factorization.

842689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2050.

The product of its digits is 27648, while the sum is 37.

The square root of 842689 is about 917.9809366212. The cubic root of 842689 is about 94.4544539436.

It can be divided in two parts, 8426 and 89, that added together give a triangular number (8515 = T₁₃₀).

The spelling of 842689 in words is "eight hundred forty-two thousand, six hundred eighty-nine".