212581812 has 24 divisors (see below), whose sum is σ = 496288800. Its totient is φ = 70822816.

The previous prime is 212581793. The next prime is 212581813. The reversal of 212581812 is 218185212.

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

It is a self number, because there is not a number n which added to its sum of digits gives 212581812.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212581813) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27514 + ... + 34382.

It is an arithmetic number, because the mean of its divisors is an integer number (20678700).

Almost surely, 2^212581812 is an apocalyptic number.

It is an amenable number.

212581812 is an abundant number, since it is smaller than the sum of its proper divisors (283706988).

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

212581812 is a wasteful number, since it uses less digits than its factorization.

212581812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9455 (or 9453 counting only the distinct ones).

The product of its digits is 2560, while the sum is 30.

The square root of 212581812 is about 14580.1855955266. The cubic root of 212581812 is about 596.8181675080.

The spelling of 212581812 in words is "two hundred twelve million, five hundred eighty-one thousand, eight hundred twelve".