423645 has 16 divisors (see below), whose sum is σ = 690432. Its totient is φ = 221760.

The previous prime is 423617. The next prime is 423649. The reversal of 423645 is 546324.

423645 = 19² + 20² + ... + 108².

It is not a de Polignac number, because 423645 - 2⁶ = 423581 is a prime.

423645 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (423649) 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, 684 + ... + 1146.

It is an arithmetic number, because the mean of its divisors is an integer number (43152).

2⁴²³⁶⁴⁵ is an apocalyptic number.

It is an amenable number.

423645 is a deficient number, since it is larger than the sum of its proper divisors (266787).

423645 is a wasteful number, since it uses less digits than its factorization.

423645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 532.

The product of its digits is 2880, while the sum is 24.

The square root of 423645 is about 650.8801733038. The cubic root of 423645 is about 75.1047425408.

Adding to 423645 its reverse (546324), we get a palindrome (969969).

The spelling of 423645 in words is "four hundred twenty-three thousand, six hundred forty-five".