1268566813 has 2 divisors, whose sum is σ = 1268566814. Its totient is φ = 1268566812.

The previous prime is 1268566799. The next prime is 1268566853. The reversal of 1268566813 is 3186658621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1253372409 + 15194404 = 35403^2 + 3898^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1268566813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1268566853) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 634283406 + 634283407.

It is an arithmetic number, because the mean of its divisors is an integer number (634283407).

Almost surely, 2^1268566813 is an apocalyptic number.

It is an amenable number.

1268566813 is a deficient number, since it is larger than the sum of its proper divisors (1).

1268566813 is an equidigital number, since it uses as much as digits as its factorization.

1268566813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 414720, while the sum is 46.

The square root of 1268566813 is about 35616.9455877396. The cubic root of 1268566813 is about 1082.5246188044.

The spelling of 1268566813 in words is "one billion, two hundred sixty-eight million, five hundred sixty-six thousand, eight hundred thirteen".