6812521812 has 18 divisors (see below), whose sum is σ = 17220541338. Its totient is φ = 2270840592.

The previous prime is 6812521783. The next prime is 6812521817. The reversal of 6812521812 is 2181252186.

It can be written as a sum of positive squares in only one way, i.e., 6373786896 + 438734916 = 79836^2 + 20946^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 189236717 = 6812521812 / (6 + 8 + 1 + 2 + 5 + 2 + 1 + 8 + 1 + 2).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6812521817) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 94618323 + ... + 94618394.

It is an arithmetic number, because the mean of its divisors is an integer number (956696741).

Almost surely, 2^6812521812 is an apocalyptic number.

It is an amenable number.

6812521812 is an abundant number, since it is smaller than the sum of its proper divisors (10408019526).

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

6812521812 is a wasteful number, since it uses less digits than its factorization.

6812521812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189236727 (or 189236722 counting only the distinct ones).

The product of its digits is 15360, while the sum is 36.

The square root of 6812521812 is about 82538.0022292762. The cubic root of 6812521812 is about 1895.6986549063.

Adding to 6812521812 its reverse (2181252186), we get a palindrome (8993773998).

The spelling of 6812521812 in words is "six billion, eight hundred twelve million, five hundred twenty-one thousand, eight hundred twelve".