421518 has 16 divisors (see below), whose sum is σ = 850176. Its totient is φ = 139320.

The previous prime is 421517. The next prime is 421559. The reversal of 421518 is 815124.

421518 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 421494 and 421503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421517) 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, 763 + ... + 1193.

It is an arithmetic number, because the mean of its divisors is an integer number (53136).

2⁴²¹⁵¹⁸ is an apocalyptic number.

421518 is an abundant number, since it is smaller than the sum of its proper divisors (428658).

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

421518 is a wasteful number, since it uses less digits than its factorization.

421518 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 599.

The product of its digits is 320, while the sum is 21.

The square root of 421518 is about 649.2441759462. The cubic root of 421518 is about 74.9788384742.

It can be divided in two parts, 421 and 518, that added together give a palindrome (939).

The spelling of 421518 in words is "four hundred twenty-one thousand, five hundred eighteen".