129866917 has 2 divisors, whose sum is σ = 129866918. Its totient is φ = 129866916.

The previous prime is 129866909. The next prime is 129866921. The reversal of 129866917 is 719668921.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 129823236 + 43681 = 11394^2 + 209^2 .

It is a cyclic number.

It is not a de Polignac number, because 129866917 - 2³ = 129866909 is a prime.

It is a super-2 number, since 2×129866917² = 33730832262169778, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (129866617) 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, 64933458 + 64933459.

It is an arithmetic number, because the mean of its divisors is an integer number (64933459).

Almost surely, 2^129866917 is an apocalyptic number.

It is an amenable number.

129866917 is a deficient number, since it is larger than the sum of its proper divisors (1).

129866917 is an equidigital number, since it uses as much as digits as its factorization.

129866917 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 326592, while the sum is 49.

The square root of 129866917 is about 11395.9166809871. The cubic root of 129866917 is about 506.4067784104.

The spelling of 129866917 in words is "one hundred twenty-nine million, eight hundred sixty-six thousand, nine hundred seventeen".