212116381 has 2 divisors, whose sum is σ = 212116382. Its totient is φ = 212116380.

The previous prime is 212116369. The next prime is 212116393. The reversal of 212116381 is 183611212.

212116381 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a balanced prime because it is at equal distance from previous prime (212116369) and next prime (212116393).

It can be written as a sum of positive squares in only one way, i.e., 146652100 + 65464281 = 12110^2 + 8091^2 .

It is a cyclic number.

It is not a de Polignac number, because 212116381 - 2¹¹ = 212114333 is a prime.

It is a super-2 number, since 2×212116381² = 89986718177074322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212113381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106058190 + 106058191.

It is an arithmetic number, because the mean of its divisors is an integer number (106058191).

Almost surely, 2^212116381 is an apocalyptic number.

It is an amenable number.

212116381 is a deficient number, since it is larger than the sum of its proper divisors (1).

212116381 is an equidigital number, since it uses as much as digits as its factorization.

212116381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 576, while the sum is 25.

The square root of 212116381 is about 14564.2157701676. The cubic root of 212116381 is about 596.3822872463.

Adding to 212116381 its reverse (183611212), we get a palindrome (395727593).

The spelling of 212116381 in words is "two hundred twelve million, one hundred sixteen thousand, three hundred eighty-one".