842439 has 8 divisors (see below), whose sum is σ = 1209712. Its totient is φ = 518400.

The previous prime is 842423. The next prime is 842447. The reversal of 842439 is 934248.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 842439 - 2⁴ = 842423 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (842419) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10762 + ... + 10839.

It is an arithmetic number, because the mean of its divisors is an integer number (151214).

2⁸⁴²⁴³⁹ is an apocalyptic number.

842439 is a deficient number, since it is larger than the sum of its proper divisors (367273).

842439 is a wasteful number, since it uses less digits than its factorization.

842439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21617.

The product of its digits is 6912, while the sum is 30.

The square root of 842439 is about 917.8447581154. The cubic root of 842439 is about 94.4451124392.

Subtracting 842439 from its reverse (934248), we obtain a square (91809 = 303²).

The spelling of 842439 in words is "eight hundred forty-two thousand, four hundred thirty-nine".