9421981 has 2 divisors, whose sum is σ = 9421982. Its totient is φ = 9421980.

The previous prime is 9421963. The next prime is 9422027. The reversal of 9421981 is 1891249.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9180900 + 241081 = 3030^2 + 491^2 .

It is an emirp because it is prime and its reverse (1891249) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9421981 - 2⁹ = 9421469 is a prime.

It is a super-2 number, since 2×9421981² = 177547451928722, which contains 22 as substring.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9421921) 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, 4710990 + 4710991.

It is an arithmetic number, because the mean of its divisors is an integer number (4710991).

Almost surely, 2^9421981 is an apocalyptic number.

It is an amenable number.

9421981 is a deficient number, since it is larger than the sum of its proper divisors (1).

9421981 is an equidigital number, since it uses as much as digits as its factorization.

9421981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5184, while the sum is 34.

The square root of 9421981 is about 3069.5245560184. The cubic root of 9421981 is about 211.2098045671.

The spelling of 9421981 in words is "nine million, four hundred twenty-one thousand, nine hundred eighty-one".