212241666 has 128 divisors (see below), whose sum is σ = 564480000. Its totient is φ = 51632640.

The previous prime is 212241661. The next prime is 212241713. The reversal of 212241666 is 666142212.

It is not an unprimeable number, because it can be changed into a prime (212241661) 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 63 ways as a sum of consecutive naturals, for example, 425085 + ... + 425583.

It is an arithmetic number, because the mean of its divisors is an integer number (4410000).

Almost surely, 2^212241666 is an apocalyptic number.

212241666 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 212241666, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (282240000).

212241666 is an abundant number, since it is smaller than the sum of its proper divisors (352238334).

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

212241666 is a wasteful number, since it uses less digits than its factorization.

212241666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 584.

The product of its digits is 6912, while the sum is 30.

The square root of 212241666 is about 14568.5162593862. The cubic root of 212241666 is about 596.4996804259.

Adding to 212241666 its reverse (666142212), we get a palindrome (878383878).

The spelling of 212241666 in words is "two hundred twelve million, two hundred forty-one thousand, six hundred sixty-six".