212439816 has 48 divisors (see below), whose sum is σ = 579524400. Its totient is φ = 70300512.

The previous prime is 212439811. The next prime is 212439827. The reversal of 212439816 is 618934212.

212439816 is a `hidden beast` number, since 212 + 439 + 8 + 1 + 6 = 666.

212439816 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×212439816² = 90261350844227712, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (212439811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 606 + ... + 20621.

It is an arithmetic number, because the mean of its divisors is an integer number (12073425).

Almost surely, 2^212439816 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 212439816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (289762200).

212439816 is an abundant number, since it is smaller than the sum of its proper divisors (367084584).

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

212439816 is a wasteful number, since it uses less digits than its factorization.

212439816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21378 (or 21371 counting only the distinct ones).

The product of its digits is 20736, while the sum is 36.

The square root of 212439816 is about 14575.3152967612. The cubic root of 212439816 is about 596.6852544934.

The spelling of 212439816 in words is "two hundred twelve million, four hundred thirty-nine thousand, eight hundred sixteen".