8172133920 has 432 divisors, whose sum is σ = 30141788040. Its totient is φ = 2015428608.

The previous prime is 8172133919. The next prime is 8172133927. The reversal of 8172133920 is 293312718.

It can be written as a sum of positive squares in 12 ways, for example, as 1170460944 + 7001672976 = 34212^2 + 83676^2 .

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

It is not an unprimeable number, because it can be changed into a prime (8172133927) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 30379546 + ... + 30379814.

Almost surely, 2^8172133920 is an apocalyptic number.

8172133920 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 8172133920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15070894020).

8172133920 is an abundant number, since it is smaller than the sum of its proper divisors (21969654120).

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

8172133920 is a wasteful number, since it uses less digits than its factorization.

8172133920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 397 (or 369 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 8172133920 is about 90399.8557520973. The cubic root of 8172133920 is about 2014.2428235494.

The spelling of 8172133920 in words is "eight billion, one hundred seventy-two million, one hundred thirty-three thousand, nine hundred twenty".