129547217 has 2 divisors, whose sum is σ = 129547218. Its totient is φ = 129547216.

The previous prime is 129547213. The next prime is 129547219. The reversal of 129547217 is 712745921.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 101626561 + 27920656 = 10081^2 + 5284^2 .

It is a cyclic number.

It is not a de Polignac number, because 129547217 - 2² = 129547213 is a prime.

Together with 129547219, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (129547213) 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, 64773608 + 64773609.

It is an arithmetic number, because the mean of its divisors is an integer number (64773609).

Almost surely, 2^129547217 is an apocalyptic number.

It is an amenable number.

129547217 is a deficient number, since it is larger than the sum of its proper divisors (1).

129547217 is an equidigital number, since it uses as much as digits as its factorization.

129547217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 35280, while the sum is 38.

The square root of 129547217 is about 11381.8810835468. The cubic root of 129547217 is about 505.9908878360.

The spelling of 129547217 in words is "one hundred twenty-nine million, five hundred forty-seven thousand, two hundred seventeen".