6403806864 has 300 divisors, whose sum is σ = 23222005884. Its totient is φ = 1688698368.

The previous prime is 6403806853. The next prime is 6403806889. The reversal of 6403806864 is 4686083046.

It can be written as a sum of positive squares in 2 ways, for example, as 3073593600 + 3330213264 = 55440^2 + 57708^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 821674 + ... + 829430.

Almost surely, 2^6403806864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6403806864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11611002942).

6403806864 is an abundant number, since it is smaller than the sum of its proper divisors (16818199020).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6403806864 is a wasteful number, since it uses less digits than its factorization.

6403806864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7804 (or 7782 counting only the distinct ones).

The product of its (nonzero) digits is 663552, while the sum is 45.

The square root of 6403806864 is about 80023.7893629138. The cubic root of 6403806864 is about 1857.0035833432.

The spelling of 6403806864 in words is "six billion, four hundred three million, eight hundred six thousand, eight hundred sixty-four".