812505218 has 16 divisors (see below), whose sum is σ = 1393568064. Its totient is φ = 348041040.

The previous prime is 812505217. The next prime is 812505247.

It is a happy number.

812505218 is nontrivially palindromic in base 10.

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

It is not an unprimeable number, because it can be changed into a prime (812505217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16421 + ... + 43527.

It is an arithmetic number, because the mean of its divisors is an integer number (87098004).

Almost surely, 2^812505218 is an apocalyptic number.

812505218 is a deficient number, since it is larger than the sum of its proper divisors (581062846).

812505218 is a wasteful number, since it uses less digits than its factorization.

812505218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29257.

The product of its (nonzero) digits is 6400, while the sum is 32.

The square root of 812505218 is about 28504.4771571064. The cubic root of 812505218 is about 933.1297867634.

It can be divided in two parts, 81250 and 5218, that added together give a palindrome (86468).

The spelling of 812505218 in words is "eight hundred twelve million, five hundred five thousand, two hundred eighteen".