8993681 has 2 divisors, whose sum is σ = 8993682. Its totient is φ = 8993680.

The previous prime is 8993609. The next prime is 8993687. The reversal of 8993681 is 1863998.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8614225 + 379456 = 2935^2 + 616^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8993681 is a prime.

It is a super-2 number, since 2×8993681² = 161772595859522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (8993687) 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, 4496840 + 4496841.

It is an arithmetic number, because the mean of its divisors is an integer number (4496841).

Almost surely, 2^8993681 is an apocalyptic number.

It is an amenable number.

8993681 is a deficient number, since it is larger than the sum of its proper divisors (1).

8993681 is an equidigital number, since it uses as much as digits as its factorization.

8993681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 93312, while the sum is 44.

The square root of 8993681 is about 2998.9466484084. The cubic root of 8993681 is about 207.9596892420.

The spelling of 8993681 in words is "eight million, nine hundred ninety-three thousand, six hundred eighty-one".