129991663 has 2 divisors, whose sum is σ = 129991664. Its totient is φ = 129991662.

The previous prime is 129991661. The next prime is 129991703. The reversal of 129991663 is 366199921.

It is a weak prime.

It is an emirp because it is prime and its reverse (366199921) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 129991663 - 2¹ = 129991661 is a prime.

Together with 129991661, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (129991661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64995831 + 64995832.

It is an arithmetic number, because the mean of its divisors is an integer number (64995832).

Almost surely, 2^129991663 is an apocalyptic number.

129991663 is a deficient number, since it is larger than the sum of its proper divisors (1).

129991663 is an equidigital number, since it uses as much as digits as its factorization.

129991663 is an evil number, because the sum of its binary digits is even.

The product of its digits is 157464, while the sum is 46.

The square root of 129991663 is about 11401.3886434943. The cubic root of 129991663 is about 506.5688725633.

The spelling of 129991663 in words is "one hundred twenty-nine million, nine hundred ninety-one thousand, six hundred sixty-three".