212542181 has 2 divisors, whose sum is σ = 212542182. Its totient is φ = 212542180.

The previous prime is 212542159. The next prime is 212542207. The reversal of 212542181 is 181245212.

212542181 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an a-pointer prime, because the next prime (212542207) can be obtained adding 212542181 to its sum of digits (26).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 212430625 + 111556 = 14575^2 + 334^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-212542181 is a prime.

It is a super-2 number, since 2×212542181² = 90348357408473522, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 212542181.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212541181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106271090 + 106271091.

It is an arithmetic number, because the mean of its divisors is an integer number (106271091).

Almost surely, 2^212542181 is an apocalyptic number.

It is an amenable number.

212542181 is a deficient number, since it is larger than the sum of its proper divisors (1).

212542181 is an equidigital number, since it uses as much as digits as its factorization.

212542181 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1280, while the sum is 26.

The square root of 212542181 is about 14578.8264616875. The cubic root of 212542181 is about 596.7810775197.

Adding to 212542181 its reverse (181245212), we get a palindrome (393787393).

The spelling of 212542181 in words is "two hundred twelve million, five hundred forty-two thousand, one hundred eighty-one".