126668681 has 2 divisors, whose sum is σ = 126668682. Its totient is φ = 126668680.

The previous prime is 126668677. The next prime is 126668719. The reversal of 126668681 is 186866621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 67240000 + 59428681 = 8200^2 + 7709^2 .

It is an emirp because it is prime and its reverse (186866621) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 126668681 - 2² = 126668677 is a prime.

It is a super-2 number, since 2×126668681² = 32089909492559522, which contains 22 as substring.

It is equal to p_7199729 and since 126668681 and 7199729 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (126628681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 63334340 + 63334341.

It is an arithmetic number, because the mean of its divisors is an integer number (63334341).

Almost surely, 2^126668681 is an apocalyptic number.

It is an amenable number.

126668681 is a deficient number, since it is larger than the sum of its proper divisors (1).

126668681 is an equidigital number, since it uses as much as digits as its factorization.

126668681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 165888, while the sum is 44.

The square root of 126668681 is about 11254.7181661737. The cubic root of 126668681 is about 502.2150803468.

The spelling of 126668681 in words is "one hundred twenty-six million, six hundred sixty-eight thousand, six hundred eighty-one".