818121216 has 160 divisors (see below), whose sum is σ = 2437718976. Its totient is φ = 241664000.

The previous prime is 818121181. The next prime is 818121221. The reversal of 818121216 is 612121818.

It is a happy number.

It is a nude number because it is divisible by every one of its digits and also a Zuckerman number because it is divisible by the product of its digits.

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

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 692146 + ... + 693326.

Almost surely, 2^818121216 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 818121216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1218859488).

818121216 is an abundant number, since it is smaller than the sum of its proper divisors (1619597760).

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

818121216 is a wasteful number, since it uses less digits than its factorization.

818121216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1254 (or 1238 counting only the distinct ones).

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

The square root of 818121216 is about 28602.8183226758. The cubic root of 818121216 is about 935.2747687791.

It can be divided in two parts, 81812 and 1216, that added together give a triangular number (83028 = T₄₀₇).

The spelling of 818121216 in words is "eight hundred eighteen million, one hundred twenty-one thousand, two hundred sixteen".