3998988864 has 126 divisors (see below), whose sum is σ = 12412227906. Its totient is φ = 1230428160.

The previous prime is 3998988859. The next prime is 3998988883. The reversal of 3998988864 is 4688898993.

3998988864 is a `hidden beast` number, since 399 + 89 + 88 + 86 + 4 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 5760000 + 3993228864 = 2400^2 + 63192^2 .

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 3998988792 and 3998988801.

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 17 ways as a sum of consecutive naturals, for example, 76804 + ... + 117884.

Almost surely, 2^3998988864 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 3998988864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6206113953).

3998988864 is an abundant number, since it is smaller than the sum of its proper divisors (8413239042).

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

3998988864 is a wasteful number, since it uses less digits than its factorization.

3998988864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41125 (or 41099 counting only the distinct ones).

The product of its digits is 214990848, while the sum is 72.

The square root of 3998988864 is about 63237.5589661714. The cubic root of 3998988864 is about 1587.2672841669.

The spelling of 3998988864 in words is "three billion, nine hundred ninety-eight million, nine hundred eighty-eight thousand, eight hundred sixty-four".