6404647 has 2 divisors, whose sum is σ = 6404648. Its totient is φ = 6404646.

The previous prime is 6404639. The next prime is 6404659. The reversal of 6404647 is 7464046.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6404647 - 2³ = 6404639 is a prime.

6404647 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6404677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3202323 + 3202324.

It is an arithmetic number, because the mean of its divisors is an integer number (3202324).

Almost surely, 2^6404647 is an apocalyptic number.

6404647 is a deficient number, since it is larger than the sum of its proper divisors (1).

6404647 is an equidigital number, since it uses as much as digits as its factorization.

6404647 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16128, while the sum is 31.

The square root of 6404647 is about 2530.7404054940. The cubic root of 6404647 is about 185.7084788548.

The spelling of 6404647 in words is "six million, four hundred four thousand, six hundred forty-seven".