8181312 has 28 divisors (see below), whose sum is σ = 21646896. Its totient is φ = 2727040.

The previous prime is 8181311. The next prime is 8181317. The reversal of 8181312 is 2131818.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (8181311) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 21114 + ... + 21497.

Almost surely, 2^8181312 is an apocalyptic number.

It is an amenable number.

8181312 is an abundant number, since it is smaller than the sum of its proper divisors (13465584).

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

8181312 is a wasteful number, since it uses less digits than its factorization.

8181312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42626 (or 42616 counting only the distinct ones).

The product of its digits is 384, while the sum is 24.

The square root of 8181312 is about 2860.2992850399. The cubic root of 8181312 is about 201.4996603220.

The spelling of 8181312 in words is "eight million, one hundred eighty-one thousand, three hundred twelve".