8981681 has 4 divisors (see below), whose sum is σ = 8987892. Its totient is φ = 8975472.

The previous prime is 8981659. The next prime is 8981689. The reversal of 8981681 is 1861898.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 5017600 + 3964081 = 2240^2 + 1991^2 .

It is a cyclic number.

It is not a de Polignac number, because 8981681 - 2⁶ = 8981617 is a prime.

It is a super-2 number, since 2×8981681² = 161341187171522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8981689) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 335 + ... + 4251.

It is an arithmetic number, because the mean of its divisors is an integer number (2246973).

Almost surely, 2^8981681 is an apocalyptic number.

It is an amenable number.

8981681 is a deficient number, since it is larger than the sum of its proper divisors (6211).

8981681 is a wasteful number, since it uses less digits than its factorization.

8981681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6210.

The product of its digits is 27648, while the sum is 41.

The square root of 8981681 is about 2996.9452781124. The cubic root of 8981681 is about 207.8671566074.

The spelling of 8981681 in words is "eight million, nine hundred eighty-one thousand, six hundred eighty-one".