421842 has 16 divisors (see below), whose sum is σ = 850752. Its totient is φ = 139440.

The previous prime is 421831. The next prime is 421847. The reversal of 421842 is 248124.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (421847) 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, 792 + ... + 1212.

It is an arithmetic number, because the mean of its divisors is an integer number (53172).

2⁴²¹⁸⁴² is an apocalyptic number.

421842 is an abundant number, since it is smaller than the sum of its proper divisors (428910).

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

421842 is a wasteful number, since it uses less digits than its factorization.

421842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 593.

The product of its digits is 512, while the sum is 21.

The square root of 421842 is about 649.4936489297. The cubic root of 421842 is about 74.9980443935.

Subtracting from 421842 its sum of digits (21), we obtain a triangular number (421821 = T₉₁₈).

Adding to 421842 its reverse (248124), we get a palindrome (669966).

The spelling of 421842 in words is "four hundred twenty-one thousand, eight hundred forty-two".