8721403920 has 320 divisors, whose sum is σ = 32114016000. Its totient is φ = 2167824384.

The previous prime is 8721403919. The next prime is 8721403939. The reversal of 8721403920 is 293041278.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4001391 + ... + 4003569.

It is an arithmetic number, because the mean of its divisors is an integer number (100356300).

Almost surely, 2^8721403920 is an apocalyptic number.

8721403920 is a gapful number since it is divisible by the number (80) 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 8721403920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16057008000).

8721403920 is an abundant number, since it is smaller than the sum of its proper divisors (23392612080).

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

8721403920 is a wasteful number, since it uses less digits than its factorization.

8721403920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2327 (or 2315 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 8721403920 is about 93388.4571025777. The cubic root of 8721403920 is about 2058.3953885069.

The spelling of 8721403920 in words is "eight billion, seven hundred twenty-one million, four hundred three thousand, nine hundred twenty".