129666643 has 2 divisors, whose sum is σ = 129666644. Its totient is φ = 129666642.

The previous prime is 129666637. The next prime is 129666679. The reversal of 129666643 is 346666921.

It is a weak prime.

It is an emirp because it is prime and its reverse (346666921) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129666643 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 129666643.

It is not a weakly prime, because it can be changed into another prime (129666683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64833321 + 64833322.

It is an arithmetic number, because the mean of its divisors is an integer number (64833322).

Almost surely, 2^129666643 is an apocalyptic number.

129666643 is a deficient number, since it is larger than the sum of its proper divisors (1).

129666643 is an equidigital number, since it uses as much as digits as its factorization.

129666643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 279936, while the sum is 43.

The square root of 129666643 is about 11387.1261958406. The cubic root of 129666643 is about 506.1463264207.

The spelling of 129666643 in words is "one hundred twenty-nine million, six hundred sixty-six thousand, six hundred forty-three".