423621 has 18 divisors (see below), whose sum is σ = 674310. Its totient is φ = 256080.

The previous prime is 423617. The next prime is 423649. The reversal of 423621 is 126324.

It is a happy number.

423621 is a `hidden beast` number, since 42 + 3 + 621 = 666.

It can be written as a sum of positive squares in only one way, i.e., 314721 + 108900 = 561^2 + 330^2 .

It is not a de Polignac number, because 423621 - 2² = 423617 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 423594 and 423603.

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 423621.

It is not an unprimeable number, because it can be changed into a prime (423601) 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 17 ways as a sum of consecutive naturals, for example, 895 + ... + 1283.

2⁴²³⁶²¹ is an apocalyptic number.

It is an amenable number.

423621 is a deficient number, since it is larger than the sum of its proper divisors (250689).

423621 is a wasteful number, since it uses less digits than its factorization.

423621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 417 (or 403 counting only the distinct ones).

The product of its digits is 288, while the sum is 18.

The square root of 423621 is about 650.8617364694. The cubic root of 423621 is about 75.1033242559.

Adding to 423621 its reverse (126324), we get a palindrome (549945).

It can be divided in two parts, 42 and 3621, that added together give a palindrome (3663).

The spelling of 423621 in words is "four hundred twenty-three thousand, six hundred twenty-one".