6442405 has 8 divisors (see below), whose sum is σ = 8185752. Its totient is φ = 4850688.

The previous prime is 6442399. The next prime is 6442427. The reversal of 6442405 is 5042446.

6442405 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 2244004 + 4198401 = 1498^2 + 2049^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6442405 is a prime.

It is a Duffinian number.

6442405 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 6442405.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 37812 + ... + 37981.

It is an arithmetic number, because the mean of its divisors is an integer number (1023219).

Almost surely, 2^6442405 is an apocalyptic number.

It is an amenable number.

6442405 is a deficient number, since it is larger than the sum of its proper divisors (1743347).

6442405 is a wasteful number, since it uses less digits than its factorization.

6442405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75815.

The product of its (nonzero) digits is 3840, while the sum is 25.

The square root of 6442405 is about 2538.1893152403. The cubic root of 6442405 is about 186.0727063813.

The spelling of 6442405 in words is "six million, four hundred forty-two thousand, four hundred five".