421568 has 28 divisors (see below), whose sum is σ = 957072. Its totient is φ = 180480.

The previous prime is 421559. The next prime is 421607. The reversal of 421568 is 865124.

It is a tau number, because it is divible by the number of its divisors (28).

Its product of digits (1920) is a multiple of the sum of its prime factors (960).

It is an unprimeable number.

421568 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, 23 + ... + 918.

2⁴²¹⁵⁶⁸ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 421568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (478536).

421568 is an abundant number, since it is smaller than the sum of its proper divisors (535504).

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

421568 is an equidigital number, since it uses as much as digits as its factorization.

421568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 960 (or 950 counting only the distinct ones).

The product of its digits is 1920, while the sum is 26.

The square root of 421568 is about 649.2826811182. The cubic root of 421568 is about 74.9818029927.

Subtracting 421568 from its reverse (865124), we obtain a square (443556 = 666²).

It can be divided in two parts, 421 and 568, that added together give a palindrome (989).

The spelling of 421568 in words is "four hundred twenty-one thousand, five hundred sixty-eight".