1286716681 has 2 divisors, whose sum is σ = 1286716682. Its totient is φ = 1286716680.

The previous prime is 1286716661. The next prime is 1286716751. The reversal of 1286716681 is 1866176821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1283072400 + 3644281 = 35820^2 + 1909^2 .

It is a cyclic number.

It is not a de Polignac number, because 1286716681 - 2⁹ = 1286716169 is a prime.

It is a super-2 number, since 2×1286716681² = 3311279634327311522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1286716601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 643358340 + 643358341.

It is an arithmetic number, because the mean of its divisors is an integer number (643358341).

Almost surely, 2^1286716681 is an apocalyptic number.

It is an amenable number.

1286716681 is a deficient number, since it is larger than the sum of its proper divisors (1).

1286716681 is an equidigital number, since it uses as much as digits as its factorization.

1286716681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 193536, while the sum is 46.

The square root of 1286716681 is about 35870.8332911294. The cubic root of 1286716681 is about 1087.6628882887.

The spelling of 1286716681 in words is "one billion, two hundred eighty-six million, seven hundred sixteen thousand, six hundred eighty-one".