9973981 has 2 divisors, whose sum is σ = 9973982. Its totient is φ = 9973980.

The previous prime is 9973967. The next prime is 9974021. The reversal of 9973981 is 1893799.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9424900 + 549081 = 3070^2 + 741^2 .

It is an emirp because it is prime and its reverse (1893799) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9973981 - 2⁷ = 9973853 is a prime.

It is a super-2 number, since 2×9973981² = 198960593976722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9973921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4986990 + 4986991.

It is an arithmetic number, because the mean of its divisors is an integer number (4986991).

Almost surely, 2^9973981 is an apocalyptic number.

It is an amenable number.

9973981 is a deficient number, since it is larger than the sum of its proper divisors (1).

9973981 is an equidigital number, since it uses as much as digits as its factorization.

9973981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 122472, while the sum is 46.

The square root of 9973981 is about 3158.1610155279. The cubic root of 9973981 is about 215.2564525893.

The spelling of 9973981 in words is "nine million, nine hundred seventy-three thousand, nine hundred eighty-one".