8917681 has 2 divisors, whose sum is σ = 8917682. Its totient is φ = 8917680.

The previous prime is 8917679. The next prime is 8917691. The reversal of 8917681 is 1867198.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8071281 + 846400 = 2841^2 + 920^2 .

It is a cyclic number.

It is not a de Polignac number, because 8917681 - 2¹ = 8917679 is a prime.

It is a super-2 number, since 2×8917681² = 159050068835522, which contains 22 as substring.

Together with 8917679, it forms a pair of twin primes.

8917681 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (8917691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4458840 + 4458841.

It is an arithmetic number, because the mean of its divisors is an integer number (4458841).

Almost surely, 2^8917681 is an apocalyptic number.

It is an amenable number.

8917681 is a deficient number, since it is larger than the sum of its proper divisors (1).

8917681 is an equidigital number, since it uses as much as digits as its factorization.

8917681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 24192, while the sum is 40.

The square root of 8917681 is about 2986.2486500625. The cubic root of 8917681 is about 207.3722521367.

The spelling of 8917681 in words is "eight million, nine hundred seventeen thousand, six hundred eighty-one".