8721131328 has 840 divisors, whose sum is σ = 34336024800. Its totient is φ = 2163345408.

The previous prime is 8721131323. The next prime is 8721131333. The reversal of 8721131328 is 8231311278.

It is an interprime number because it is at equal distance from previous prime (8721131323) and next prime (8721131333).

It is a Harshad number since it is a multiple of its sum of digits (36).

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 = 8721131292 and 8721131301.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8721131323) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 62741883 + ... + 62742021.

It is an arithmetic number, because the mean of its divisors is an integer number (40876220).

Almost surely, 2^8721131328 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 8721131328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17168012400).

8721131328 is an abundant number, since it is smaller than the sum of its proper divisors (25614893472).

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

8721131328 is a wasteful number, since it uses less digits than its factorization.

8721131328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209 (or 183 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 8721131328 is about 93386.9976388576. The cubic root of 8721131328 is about 2058.3739428785.

The spelling of 8721131328 in words is "eight billion, seven hundred twenty-one million, one hundred thirty-one thousand, three hundred twenty-eight".