4042405 has 4 divisors (see below), whose sum is σ = 4850892. Its totient is φ = 3233920.

The previous prime is 4042393. The next prime is 4042417. The reversal of 4042405 is 5042404.

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

It is an interprime number because it is at equal distance from previous prime (4042393) and next prime (4042417).

It can be written as a sum of positive squares in 2 ways, for example, as 481636 + 3560769 = 694^2 + 1887^2 .

It is not a de Polignac number, because 4042405 - 2¹⁹ = 3518117 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 404236 + ... + 404245.

It is an arithmetic number, because the mean of its divisors is an integer number (1212723).

Almost surely, 2^4042405 is an apocalyptic number.

It is an amenable number.

4042405 is a deficient number, since it is larger than the sum of its proper divisors (808487).

4042405 is an equidigital number, since it uses as much as digits as its factorization.

4042405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 808486.

The product of its (nonzero) digits is 640, while the sum is 19.

The square root of 4042405 is about 2010.5733013248. The cubic root of 4042405 is about 159.2990823869.

Adding to 4042405 its reverse (5042404), we get a palindrome (9084809).

Subtracting 4042405 from its reverse (5042404), we obtain a palindrome (999999).

It can be divided in two parts, 404 and 2405, that added together give a square (2809 = 53²).

The spelling of 4042405 in words is "four million, forty-two thousand, four hundred five".