6447855 has 16 divisors (see below), whose sum is σ = 10442880. Its totient is φ = 3396768.

The previous prime is 6447853. The next prime is 6447899. The reversal of 6447855 is 5587446.

It is not a de Polignac number, because 6447855 - 2¹ = 6447853 is a prime.

It is a d-powerful number, because it can be written as 6² + 4³ + 4¹¹ + 7² + 8⁷ + 5⁷ + 5⁷ .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6447853) 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 15 ways as a sum of consecutive naturals, for example, 1345 + ... + 3834.

It is an arithmetic number, because the mean of its divisors is an integer number (652680).

Almost surely, 2^6447855 is an apocalyptic number.

6447855 is a deficient number, since it is larger than the sum of its proper divisors (3995025).

6447855 is a wasteful number, since it uses less digits than its factorization.

6447855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5270.

The product of its digits is 134400, while the sum is 39.

The square root of 6447855 is about 2539.2626882621. The cubic root of 6447855 is about 186.1251614517.

The spelling of 6447855 in words is "six million, four hundred forty-seven thousand, eight hundred fifty-five".