6446781807 has 16 divisors (see below), whose sum is σ = 8709120000. Its totient is φ = 4241206944.

The previous prime is 6446781797. The next prime is 6446781827. The reversal of 6446781807 is 7081876446.

It is a happy number.

It is not a de Polignac number, because 6446781807 - 2³⁰ = 5373039983 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6446781807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6446781827) 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, 524569 + ... + 536717.

It is an arithmetic number, because the mean of its divisors is an integer number (544320000).

Almost surely, 2^6446781807 is an apocalyptic number.

6446781807 is a deficient number, since it is larger than the sum of its proper divisors (2262338193).

6446781807 is a wasteful number, since it uses less digits than its factorization.

6446781807 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14470.

The product of its (nonzero) digits is 1806336, while the sum is 51.

The square root of 6446781807 is about 80291.8539267839. The cubic root of 6446781807 is about 1861.1483453921.

The spelling of 6446781807 in words is "six billion, four hundred forty-six million, seven hundred eighty-one thousand, eight hundred seven".