6404643 has 48 divisors (see below), whose sum is σ = 11381760. Its totient is φ = 3547152.

The previous prime is 6404639. The next prime is 6404647. The reversal of 6404643 is 3464046.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (6404639) and next prime (6404647).

It is not a de Polignac number, because 6404643 - 2² = 6404639 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (6404647) 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 47 ways as a sum of consecutive naturals, for example, 62130 + ... + 62232.

It is an arithmetic number, because the mean of its divisors is an integer number (237120).

Almost surely, 2^6404643 is an apocalyptic number.

6404643 is a gapful number since it is divisible by the number (63) formed by its first and last digit.

6404643 is a deficient number, since it is larger than the sum of its proper divisors (4977117).

6404643 is a wasteful number, since it uses less digits than its factorization.

6404643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173 (or 160 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 27.

The square root of 6404643 is about 2530.7396152113. The cubic root of 6404643 is about 185.7084401936.

Adding to 6404643 its reverse (3464046), we get a palindrome (9868689).

The spelling of 6404643 in words is "six million, four hundred four thousand, six hundred forty-three".