8543984681 has 2 divisors, whose sum is σ = 8543984682. Its totient is φ = 8543984680.

The previous prime is 8543984651. The next prime is 8543984747. The reversal of 8543984681 is 1864893458.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7519664656 + 1024320025 = 86716^2 + 32005^2 .

It is a cyclic number.

It is not a de Polignac number, because 8543984681 - 2²² = 8539790377 is a prime.

It is a super-2 number, since 2×8543984681² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (8543984651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4271992340 + 4271992341.

It is an arithmetic number, because the mean of its divisors is an integer number (4271992341).

Almost surely, 2^8543984681 is an apocalyptic number.

It is an amenable number.

8543984681 is a deficient number, since it is larger than the sum of its proper divisors (1).

8543984681 is an equidigital number, since it uses as much as digits as its factorization.

8543984681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6635520, while the sum is 56.

The square root of 8543984681 is about 92433.6772015481. The cubic root of 8543984681 is about 2044.3416983092.

The spelling of 8543984681 in words is "eight billion, five hundred forty-three million, nine hundred eighty-four thousand, six hundred eighty-one".