129542549 has 2 divisors, whose sum is σ = 129542550. Its totient is φ = 129542548.

The previous prime is 129542519. The next prime is 129542593. The reversal of 129542549 is 945245921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 126000625 + 3541924 = 11225^2 + 1882^2 .

It is an emirp because it is prime and its reverse (945245921) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 129542549 - 2²⁴ = 112765333 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (129542519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64771274 + 64771275.

It is an arithmetic number, because the mean of its divisors is an integer number (64771275).

Almost surely, 2^129542549 is an apocalyptic number.

It is an amenable number.

129542549 is a deficient number, since it is larger than the sum of its proper divisors (1).

129542549 is an equidigital number, since it uses as much as digits as its factorization.

129542549 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 129600, while the sum is 41.

The square root of 129542549 is about 11381.6760189350. The cubic root of 129542549 is about 505.9848102738.

The spelling of 129542549 in words is "one hundred twenty-nine million, five hundred forty-two thousand, five hundred forty-nine".