211420213981 has 2 divisors, whose sum is σ = 211420213982. Its totient is φ = 211420213980.

The previous prime is 211420213957. The next prime is 211420214021. The reversal of 211420213981 is 189312024112.

211420213981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 210355236025 + 1064977956 = 458645^2 + 32634^2 .

It is a cyclic number.

It is not a de Polignac number, because 211420213981 - 2¹⁵ = 211420181213 is a prime.

It is a super-2 number, since 2×211420213981² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211420213181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105710106990 + 105710106991.

It is an arithmetic number, because the mean of its divisors is an integer number (105710106991).

Almost surely, 2^211420213981 is an apocalyptic number.

It is an amenable number.

211420213981 is a deficient number, since it is larger than the sum of its proper divisors (1).

211420213981 is an equidigital number, since it uses as much as digits as its factorization.

211420213981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6912, while the sum is 34.

The spelling of 211420213981 in words is "two hundred eleven billion, four hundred twenty million, two hundred thirteen thousand, nine hundred eighty-one".