8161408520 has 64 divisors (see below), whose sum is σ = 19354950000. Its totient is φ = 3092497408.

The previous prime is 8161408517. The next prime is 8161408529. The reversal of 8161408520 is 258041618.

It can be written as a sum of positive squares in 8 ways, for example, as 5828711716 + 2332696804 = 76346^2 + 48298^2 .

It is not an unprimeable number, because it can be changed into a prime (8161408529) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4895 + ... + 127854.

Almost surely, 2^8161408520 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 8161408520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9677475000).

8161408520 is an abundant number, since it is smaller than the sum of its proper divisors (11193541480).

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

8161408520 is a wasteful number, since it uses less digits than its factorization.

8161408520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132842 (or 132838 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 35.

The square root of 8161408520 is about 90340.5142779252. The cubic root of 8161408520 is about 2013.3612497287.

The spelling of 8161408520 in words is "eight billion, one hundred sixty-one million, four hundred eight thousand, five hundred twenty".