20843000681 has 2 divisors, whose sum is σ = 20843000682. Its totient is φ = 20843000680.

The previous prime is 20843000641. The next prime is 20843000743. The reversal of 20843000681 is 18600034802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11456491225 + 9386509456 = 107035^2 + 96884^2 .

It is a cyclic number.

It is not a de Polignac number, because 20843000681 - 2¹⁰ = 20842999657 is a prime.

It is a super-2 number, since 2×20843000681² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20843000621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10421500340 + 10421500341.

It is an arithmetic number, because the mean of its divisors is an integer number (10421500341).

Almost surely, 2^20843000681 is an apocalyptic number.

It is an amenable number.

20843000681 is a deficient number, since it is larger than the sum of its proper divisors (1).

20843000681 is an equidigital number, since it uses as much as digits as its factorization.

20843000681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9216, while the sum is 32.

The spelling of 20843000681 in words is "twenty billion, eight hundred forty-three million, six hundred eighty-one", and thus it is an aban number.