9916681 has 2 divisors, whose sum is σ = 9916682. Its totient is φ = 9916680.

The previous prime is 9916679. The next prime is 9916691. The reversal of 9916681 is 1866199.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6734025 + 3182656 = 2595^2 + 1784^2 .

It is a cyclic number.

It is not a de Polignac number, because 9916681 - 2¹ = 9916679 is a prime.

It is a super-2 number, since 2×9916681² = 196681124111522, which contains 22 as substring.

Together with 9916679, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (9916631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4958340 + 4958341.

It is an arithmetic number, because the mean of its divisors is an integer number (4958341).

Almost surely, 2^9916681 is an apocalyptic number.

It is an amenable number.

9916681 is a deficient number, since it is larger than the sum of its proper divisors (1).

9916681 is an equidigital number, since it uses as much as digits as its factorization.

9916681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23328, while the sum is 40.

The square root of 9916681 is about 3149.0762137490. The cubic root of 9916681 is about 214.8434483209.

The spelling of 9916681 in words is "nine million, nine hundred sixteen thousand, six hundred eighty-one".