8199170820 has 72 divisors (see below), whose sum is σ = 24925020120. Its totient is φ = 2181680640.

The previous prime is 8199170797. The next prime is 8199170827. The reversal of 8199170820 is 280719918.

It can be written as a sum of positive squares in 4 ways, for example, as 51581124 + 8147589696 = 7182^2 + 90264^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (8199170827) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 33576 + ... + 132384.

It is an arithmetic number, because the mean of its divisors is an integer number (346180835).

Almost surely, 2^8199170820 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 8199170820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12462510060).

8199170820 is an abundant number, since it is smaller than the sum of its proper divisors (16725849300).

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

8199170820 is a wasteful number, since it uses less digits than its factorization.

8199170820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99285 (or 99280 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 45.

The square root of 8199170820 is about 90549.2728849879. The cubic root of 8199170820 is about 2016.4617027612.

The spelling of 8199170820 in words is "eight billion, one hundred ninety-nine million, one hundred seventy thousand, eight hundred twenty".