3999128640 has 224 divisors, whose sum is σ = 13779642240. Its totient is φ = 976797696.

The previous prime is 3999128537. The next prime is 3999128687. The reversal of 3999128640 is 468219993.

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 31 ways as a sum of consecutive naturals, for example, 1708591 + ... + 1710929.

It is an arithmetic number, because the mean of its divisors is an integer number (61516260).

Almost surely, 2^3999128640 is an apocalyptic number.

3999128640 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3999128640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6889821120).

3999128640 is an abundant number, since it is smaller than the sum of its proper divisors (9780513600).

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

3999128640 is a wasteful number, since it uses less digits than its factorization.

3999128640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2509 (or 2499 counting only the distinct ones).

The product of its (nonzero) digits is 839808, while the sum is 51.

The square root of 3999128640 is about 63238.6641225129. The cubic root of 3999128640 is about 1587.2857771156.

The spelling of 3999128640 in words is "three billion, nine hundred ninety-nine million, one hundred twenty-eight thousand, six hundred forty".