3999185568 has 144 divisors (see below), whose sum is σ = 13568808960. Its totient is φ = 1142612352.

The previous prime is 3999185563. The next prime is 3999185611. The reversal of 3999185568 is 8655819993.

3999185568 is a `hidden beast` number, since 399 + 9 + 185 + 5 + 68 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (3999185563) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4896 + ... + 89567.

It is an arithmetic number, because the mean of its divisors is an integer number (94227840).

Almost surely, 2^3999185568 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 3999185568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6784404480).

3999185568 is an abundant number, since it is smaller than the sum of its proper divisors (9569623392).

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

3999185568 is a wasteful number, since it uses less digits than its factorization.

3999185568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94496 (or 94475 counting only the distinct ones).

The product of its digits is 20995200, while the sum is 63.

The square root of 3999185568 is about 63239.1142252957. The cubic root of 3999185568 is about 1587.2933088043.

The spelling of 3999185568 in words is "three billion, nine hundred ninety-nine million, one hundred eighty-five thousand, five hundred sixty-eight".