8115991290 has 128 divisors (see below), whose sum is σ = 23715244800. Its totient is φ = 1958757120.

The previous prime is 8115991271. The next prime is 8115991309. The reversal of 8115991290 is 921995118.

It is an interprime number because it is at equal distance from previous prime (8115991271) and next prime (8115991309).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 674164 + ... + 686096.

It is an arithmetic number, because the mean of its divisors is an integer number (185275350).

Almost surely, 2^8115991290 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 8115991290, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11857622400).

8115991290 is an abundant number, since it is smaller than the sum of its proper divisors (15599253510).

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

8115991290 is a wasteful number, since it uses less digits than its factorization.

8115991290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12189 (or 12183 counting only the distinct ones).

The product of its (nonzero) digits is 58320, while the sum is 45.

The square root of 8115991290 is about 90088.7966952606. The cubic root of 8115991290 is about 2009.6195983170.

The spelling of 8115991290 in words is "eight billion, one hundred fifteen million, nine hundred ninety-one thousand, two hundred ninety".