6399833440 has 384 divisors, whose sum is σ = 20971560960. Its totient is φ = 1780531200.

The previous prime is 6399833437. The next prime is 6399833509. The reversal of 6399833440 is 443389936.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4964316 + ... + 4965604.

It is an arithmetic number, because the mean of its divisors is an integer number (54613440).

Almost surely, 2^6399833440 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 6399833440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10485780480).

6399833440 is an abundant number, since it is smaller than the sum of its proper divisors (14571727520).

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

6399833440 is a wasteful number, since it uses less digits than its factorization.

6399833440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1366 (or 1358 counting only the distinct ones).

The product of its (nonzero) digits is 1679616, while the sum is 49.

The square root of 6399833440 is about 79998.9589932269. The cubic root of 6399833440 is about 1856.6194269921.

The spelling of 6399833440 in words is "six billion, three hundred ninety-nine million, eight hundred thirty-three thousand, four hundred forty".