3999044640 has 192 divisors, whose sum is σ = 13769118720. Its totient is φ = 971243520.

The previous prime is 3999044597. The next prime is 3999044681. The reversal of 3999044640 is 464409993.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 3999044640.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 245056 + ... + 260864.

It is an arithmetic number, because the mean of its divisors is an integer number (71714160).

Almost surely, 2^3999044640 is an apocalyptic number.

3999044640 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 3999044640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6884559360).

3999044640 is an abundant number, since it is smaller than the sum of its proper divisors (9770074080).

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

3999044640 is a wasteful number, since it uses less digits than its factorization.

3999044640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15875 (or 15867 counting only the distinct ones).

The product of its (nonzero) digits is 839808, while the sum is 48.

The square root of 3999044640 is about 63237.9999683734. Note that the first 4 decimals coincide. The cubic root of 3999044640 is about 1587.2746636164.

The spelling of 3999044640 in words is "three billion, nine hundred ninety-nine million, forty-four thousand, six hundred forty".