1266548681 has 2 divisors, whose sum is σ = 1266548682. Its totient is φ = 1266548680.

The previous prime is 1266548669. The next prime is 1266548711. The reversal of 1266548681 is 1868456621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 811110400 + 455438281 = 28480^2 + 21341^2 .

It is a cyclic number.

It is not a de Polignac number, because 1266548681 - 2¹⁴ = 1266532297 is a prime.

It is a super-2 number, since 2×1266548681² = 3208291122685679522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1266548641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 633274340 + 633274341.

It is an arithmetic number, because the mean of its divisors is an integer number (633274341).

Almost surely, 2^1266548681 is an apocalyptic number.

It is an amenable number.

1266548681 is a deficient number, since it is larger than the sum of its proper divisors (1).

1266548681 is an equidigital number, since it uses as much as digits as its factorization.

1266548681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 552960, while the sum is 47.

The square root of 1266548681 is about 35588.6032459831. The cubic root of 1266548681 is about 1081.9502601152.

The spelling of 1266548681 in words is "one billion, two hundred sixty-six million, five hundred forty-eight thousand, six hundred eighty-one".