6404431 has 4 divisors (see below), whose sum is σ = 6986664. Its totient is φ = 5822200.

The previous prime is 6404407. The next prime is 6404449. The reversal of 6404431 is 1344046.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 6404431 - 2⁷ = 6404303 is a prime.

It is a super-2 number, since 2×6404431² = 82033472867522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6404401) 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 3 ways as a sum of consecutive naturals, for example, 291100 + ... + 291121.

It is an arithmetic number, because the mean of its divisors is an integer number (1746666).

Almost surely, 2^6404431 is an apocalyptic number.

6404431 is a deficient number, since it is larger than the sum of its proper divisors (582233).

6404431 is a wasteful number, since it uses less digits than its factorization.

6404431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 582232.

The product of its (nonzero) digits is 1152, while the sum is 22.

The square root of 6404431 is about 2530.6977298761. The cubic root of 6404431 is about 185.7063911268.

Adding to 6404431 its reverse (1344046), we get a palindrome (7748477).

The spelling of 6404431 in words is "six million, four hundred four thousand, four hundred thirty-one".