6440406336 has 336 divisors, whose sum is σ = 23723071680. Its totient is φ = 1698278400.

The previous prime is 6440406319. The next prime is 6440406359. The reversal of 6440406336 is 6336040446.

6440406336 is a `hidden beast` number, since 644 + 0 + 4 + 0 + 6 + 3 + 3 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (336).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 6440406336.

It is a congruent number.

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 47 ways as a sum of consecutive naturals, for example, 1097811 + ... + 1103661.

It is an arithmetic number, because the mean of its divisors is an integer number (70604380).

Almost surely, 2^6440406336 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 6440406336, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11861535840).

6440406336 is an abundant number, since it is smaller than the sum of its proper divisors (17282665344).

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

6440406336 is a wasteful number, since it uses less digits than its factorization.

6440406336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5899 (or 5876 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 36.

The square root of 6440406336 is about 80252.1422517804. The cubic root of 6440406336 is about 1860.5346225926.

The spelling of 6440406336 in words is "six billion, four hundred forty million, four hundred six thousand, three hundred thirty-six".