8181812 has 12 divisors (see below), whose sum is σ = 14349216. Its totient is φ = 4082040.

The previous prime is 8181809. The next prime is 8181821. The reversal of 8181812 is 2181818.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 137 + ... + 4047.

It is an arithmetic number, because the mean of its divisors is an integer number (1195768).

Almost surely, 2^8181812 is an apocalyptic number.

It is an amenable number.

8181812 is a deficient number, since it is larger than the sum of its proper divisors (6167404).

8181812 is a wasteful number, since it uses less digits than its factorization.

8181812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4438 (or 4436 counting only the distinct ones).

The product of its digits is 1024, while the sum is 29.

The square root of 8181812 is about 2860.3866871456. The cubic root of 8181812 is about 201.5037651151.

The spelling of 8181812 in words is "eight million, one hundred eighty-one thousand, eight hundred twelve".