212011381 has 2 divisors, whose sum is σ = 212011382. Its totient is φ = 212011380.

The previous prime is 212011357. The next prime is 212011421. The reversal of 212011381 is 183110212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 184280625 + 27730756 = 13575^2 + 5266^2 .

It is a cyclic number.

It is not a de Polignac number, because 212011381 - 2¹³ = 212003189 is a prime.

It is a super-2 number, since 2×212011381² = 89897651347054322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212311381) 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 as a sum of consecutive naturals, namely, 106005690 + 106005691.

It is an arithmetic number, because the mean of its divisors is an integer number (106005691).

Almost surely, 2^212011381 is an apocalyptic number.

It is an amenable number.

212011381 is a deficient number, since it is larger than the sum of its proper divisors (1).

212011381 is an equidigital number, since it uses as much as digits as its factorization.

212011381 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 19.

The square root of 212011381 is about 14560.6105984605. The cubic root of 212011381 is about 596.2838656860.

Adding to 212011381 its reverse (183110212), we get a palindrome (395121593).

The spelling of 212011381 in words is "two hundred twelve million, eleven thousand, three hundred eighty-one".