129487609 has 2 divisors, whose sum is σ = 129487610. Its totient is φ = 129487608.

The previous prime is 129487607. The next prime is 129487621. The reversal of 129487609 is 906784921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 93547584 + 35940025 = 9672^2 + 5995^2 .

It is a cyclic number.

It is not a de Polignac number, because 129487609 - 2¹ = 129487607 is a prime.

Together with 129487607, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (129487607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64743804 + 64743805.

It is an arithmetic number, because the mean of its divisors is an integer number (64743805).

Almost surely, 2^129487609 is an apocalyptic number.

It is an amenable number.

129487609 is a deficient number, since it is larger than the sum of its proper divisors (1).

129487609 is an equidigital number, since it uses as much as digits as its factorization.

129487609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 217728, while the sum is 46.

The square root of 129487609 is about 11379.2622344333. The cubic root of 129487609 is about 505.9132694647.

The spelling of 129487609 in words is "one hundred twenty-nine million, four hundred eighty-seven thousand, six hundred nine".