842420 has 24 divisors (see below), whose sum is σ = 1796424. Its totient is φ = 331776.

The previous prime is 842419. The next prime is 842423. The reversal of 842420 is 24248.

It can be written as a sum of positive squares in 4 ways, for example, as 355216 + 487204 = 596^2 + 698^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 842392 and 842401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (842423) 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 7 ways as a sum of consecutive naturals, for example, 1172 + ... + 1748.

It is an arithmetic number, because the mean of its divisors is an integer number (74851).

2⁸⁴²⁴²⁰ is an apocalyptic number.

It is an amenable number.

842420 is an abundant number, since it is smaller than the sum of its proper divisors (954004).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

842420 is a wasteful number, since it uses less digits than its factorization.

842420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 659 (or 657 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 20.

The square root of 842420 is about 917.8344077229. The cubic root of 842420 is about 94.4444024093. Note that the first 4 decimals are identical.

Adding to 842420 its reverse (24248), we get a palindrome (866668).

The spelling of 842420 in words is "eight hundred forty-two thousand, four hundred twenty".