3944816640 has 560 divisors, whose sum is σ = 14986513080. Its totient is φ = 990904320.

The previous prime is 3944816639. The next prime is 3944816647. The reversal of 3944816640 is 466184493.

3944816640 is a `hidden beast` number, since 3 + 9 + 448 + 166 + 40 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 2176782336 + 1768034304 = 46656^2 + 42048^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (3944816647) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 96215020 + ... + 96215060.

Almost surely, 2^3944816640 is an apocalyptic number.

3944816640 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 3944816640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7493256540).

3944816640 is an abundant number, since it is smaller than the sum of its proper divisors (11041696440).

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

3944816640 is an equidigital number, since it uses as much as digits as its factorization.

3944816640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113 (or 80 counting only the distinct ones).

The product of its (nonzero) digits is 497664, while the sum is 45.

The square root of 3944816640 is about 62807.7753148446. The cubic root of 3944816640 is about 1580.0673794905.

The spelling of 3944816640 in words is "three billion, nine hundred forty-four million, eight hundred sixteen thousand, six hundred forty".