842609 has 4 divisors (see below), whose sum is σ = 845040. Its totient is φ = 840180.

The previous prime is 842599. The next prime is 842617. The reversal of 842609 is 906248.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 842609 - 2⁸ = 842353 is a prime.

It is a Duffinian number.

It is a plaindrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (842209) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 587 + ... + 1424.

It is an arithmetic number, because the mean of its divisors is an integer number (211260).

2⁸⁴²⁶⁰⁹ is an apocalyptic number.

It is an amenable number.

842609 is a deficient number, since it is larger than the sum of its proper divisors (2431).

842609 is a wasteful number, since it uses less digits than its factorization.

842609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2430.

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 842609 is about 917.9373616974. The cubic root of 842609 is about 94.4514648632.

The spelling of 842609 in words is "eight hundred forty-two thousand, six hundred nine".