421365 has 16 divisors (see below), whose sum is σ = 770688. Its totient is φ = 192576.

The previous prime is 421361. The next prime is 421381. The reversal of 421365 is 563124.

It is a happy number.

It is not a de Polignac number, because 421365 - 2² = 421361 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 421365.

It is not an unprimeable number, because it can be changed into a prime (421361) 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 15 ways as a sum of consecutive naturals, for example, 1902 + ... + 2111.

It is an arithmetic number, because the mean of its divisors is an integer number (48168).

2⁴²¹³⁶⁵ is an apocalyptic number.

It is an amenable number.

421365 is a deficient number, since it is larger than the sum of its proper divisors (349323).

421365 is a wasteful number, since it uses less digits than its factorization.

421365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4028.

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

The square root of 421365 is about 649.1263359316. The cubic root of 421365 is about 74.9697655912.

Adding to 421365 its reverse (563124), we get a palindrome (984489).

It can be divided in two parts, 4213 and 65, that added together give a triangular number (4278 = T₉₂).

The spelling of 421365 in words is "four hundred twenty-one thousand, three hundred sixty-five".