4005000000 has 336 divisors, whose sum is σ = 14510705040. Its totient is φ = 1056000000.

The previous prime is 4004999993. The next prime is 4005000023. The reversal of 4005000000 is 5004.

It can be written as a sum of positive squares in 8 ways, for example, as 2489610816 + 1515389184 = 49896^2 + 38928^2 .

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 44999956 + ... + 45000044.

Almost surely, 2^4005000000 is an apocalyptic number.

4005000000 is a gapful number since it is divisible by the number (40) 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 4005000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7255352520).

4005000000 is an abundant number, since it is smaller than the sum of its proper divisors (10505705040).

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

4005000000 is an frugal number, since it uses more digits than its factorization.

4005000000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142 (or 99 counting only the distinct ones).

The product of its (nonzero) digits is 20, while the sum is 9.

The square root of 4005000000 is about 63285.0693291870. The cubic root of 4005000000 is about 1588.0621936739.

Adding to 4005000000 its reverse (5004), we get a palindrome (4005005004).

The spelling of 4005000000 in words is "four billion, five million", and thus it is an aban number.