6639706400 has 72 divisors (see below), whose sum is σ = 16243960320. Its totient is φ = 2650184960.

The previous prime is 6639706399. The next prime is 6639706421. The reversal of 6639706400 is 46079366.

It is a happy number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 374537 + ... + 391863.

It is an arithmetic number, because the mean of its divisors is an integer number (225610560).

Almost surely, 2^6639706400 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 6639706400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8121980160).

6639706400 is an abundant number, since it is smaller than the sum of its proper divisors (9604253920).

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

6639706400 is a wasteful number, since it uses less digits than its factorization.

6639706400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17826 (or 17813 counting only the distinct ones).

The product of its (nonzero) digits is 163296, while the sum is 41.

The square root of 6639706400 is about 81484.3935977927. The cubic root of 6639706400 is about 1879.5315718412.

The spelling of 6639706400 in words is "six billion, six hundred thirty-nine million, seven hundred six thousand, four hundred".