8121861120 has 352 divisors, whose sum is σ = 27599717376. Its totient is φ = 2034892800.

The previous prime is 8121861079. The next prime is 8121861161. The reversal of 8121861120 is 211681218.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (8121861079) and next prime (8121861161).

It is a Harshad number since it is a multiple of its sum of digits (30).

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 31 ways as a sum of consecutive naturals, for example, 17617690 + ... + 17618150.

It is an arithmetic number, because the mean of its divisors is an integer number (78408288).

Almost surely, 2^8121861120 is an apocalyptic number.

8121861120 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 8121861120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13799858688).

8121861120 is an abundant number, since it is smaller than the sum of its proper divisors (19477856256).

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

8121861120 is a wasteful number, since it uses less digits than its factorization.

8121861120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 557 (or 539 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 30.

The square root of 8121861120 is about 90121.3688311490. The cubic root of 8121861120 is about 2010.1039623463.

The spelling of 8121861120 in words is "eight billion, one hundred twenty-one million, eight hundred sixty-one thousand, one hundred twenty".