421563 has 4 divisors (see below), whose sum is σ = 562088. Its totient is φ = 281040.

The previous prime is 421559. The next prime is 421607. The reversal of 421563 is 365124.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 421563 - 2² = 421559 is a prime.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (421163) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 70258 + ... + 70263.

It is an arithmetic number, because the mean of its divisors is an integer number (140522).

2⁴²¹⁵⁶³ is an apocalyptic number.

421563 is a deficient number, since it is larger than the sum of its proper divisors (140525).

421563 is a wasteful number, since it uses less digits than its factorization.

421563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140524.

The product of its digits is 720, while the sum is 21.

The square root of 421563 is about 649.2788307037. The cubic root of 421563 is about 74.9815065514.

Adding to 421563 its reverse (365124), we get a palindrome (786687).

It can be divided in two parts, 4215 and 63, that added together give a triangular number (4278 = T₉₂).

The spelling of 421563 in words is "four hundred twenty-one thousand, five hundred sixty-three".