7989391872 has 720 divisors, whose sum is σ = 30564293760. Its totient is φ = 1962639360.

The previous prime is 7989391847. The next prime is 7989391903. The reversal of 7989391872 is 2781939897.

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

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 89768404 + ... + 89768492.

It is an arithmetic number, because the mean of its divisors is an integer number (42450408).

Almost surely, 2^7989391872 is an apocalyptic number.

7989391872 is a gapful number since it is divisible by the number (72) 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 7989391872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15282146880).

7989391872 is an abundant number, since it is smaller than the sum of its proper divisors (22574901888).

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

7989391872 is a wasteful number, since it uses less digits than its factorization.

7989391872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165 (or 135 counting only the distinct ones).

The product of its digits is 13716864, while the sum is 63.

The square root of 7989391872 is about 89383.3981900442. The cubic root of 7989391872 is about 1999.1155983078.

The spelling of 7989391872 in words is "seven billion, nine hundred eighty-nine million, three hundred ninety-one thousand, eight hundred seventy-two".