214105981 has 2 divisors, whose sum is σ = 214105982. Its totient is φ = 214105980.

The previous prime is 214105979. The next prime is 214106021. The reversal of 214105981 is 189501412.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 111408025 + 102697956 = 10555^2 + 10134^2 .

It is a cyclic number.

It is not a de Polignac number, because 214105981 - 2¹ = 214105979 is a prime.

It is a super-2 number, since 2×214105981² = 91682742199944722, which contains 22 as substring.

Together with 214105979, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (214105681) 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, 107052990 + 107052991.

It is an arithmetic number, because the mean of its divisors is an integer number (107052991).

Almost surely, 2^214105981 is an apocalyptic number.

It is an amenable number.

214105981 is a deficient number, since it is larger than the sum of its proper divisors (1).

214105981 is an equidigital number, since it uses as much as digits as its factorization.

214105981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2880, while the sum is 31.

The square root of 214105981 is about 14632.3607459630. The cubic root of 214105981 is about 598.2411276889.

The spelling of 214105981 in words is "two hundred fourteen million, one hundred five thousand, nine hundred eighty-one".