421918 has 8 divisors (see below), whose sum is σ = 723312. Its totient is φ = 180816.

The previous prime is 421913. The next prime is 421943. The reversal of 421918 is 819124.

It is a happy number.

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

It is a junction number, because it is equal to n+sod(n) for n = 421892 and 421901.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421913) by changing a digit.

421918 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15055 + ... + 15082.

It is an arithmetic number, because the mean of its divisors is an integer number (90414).

2⁴²¹⁹¹⁸ is an apocalyptic number.

421918 is a deficient number, since it is larger than the sum of its proper divisors (301394).

421918 is a wasteful number, since it uses less digits than its factorization.

421918 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30146.

The product of its digits is 576, while the sum is 25.

The square root of 421918 is about 649.5521534103. The cubic root of 421918 is about 75.0025480616.

The spelling of 421918 in words is "four hundred twenty-one thousand, nine hundred eighteen".