212242081 has 4 divisors (see below), whose sum is σ = 212274964. Its totient is φ = 212209200.

The previous prime is 212242073. The next prime is 212242099. The reversal of 212242081 is 180242212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 185368225 + 26873856 = 13615^2 + 5184^2 .

It is a cyclic number.

It is not a de Polignac number, because 212242081 - 2³ = 212242073 is a prime.

It is a super-2 number, since 2×212242081² = 90093401894421122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (212242001) 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 3 ways as a sum of consecutive naturals, for example, 3210 + ... + 20851.

It is an arithmetic number, because the mean of its divisors is an integer number (53068741).

Almost surely, 2^212242081 is an apocalyptic number.

It is an amenable number.

212242081 is a deficient number, since it is larger than the sum of its proper divisors (32883).

212242081 is an equidigital number, since it uses as much as digits as its factorization.

212242081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32882.

The product of its (nonzero) digits is 512, while the sum is 22.

The square root of 212242081 is about 14568.5305024220. The cubic root of 212242081 is about 596.5000692078.

Adding to 212242081 its reverse (180242212), we get a palindrome (392484293).

The spelling of 212242081 in words is "two hundred twelve million, two hundred forty-two thousand, eighty-one".