129556169 has 2 divisors, whose sum is σ = 129556170. Its totient is φ = 129556168.

The previous prime is 129556159. The next prime is 129556211. The reversal of 129556169 is 961655921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 75342400 + 54213769 = 8680^2 + 7363^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129556169 is a prime.

It is a super-2 number, since 2×129556169² = 33569601851913122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (129556109) 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, 64778084 + 64778085.

It is an arithmetic number, because the mean of its divisors is an integer number (64778085).

Almost surely, 2^129556169 is an apocalyptic number.

It is an amenable number.

129556169 is a deficient number, since it is larger than the sum of its proper divisors (1).

129556169 is an equidigital number, since it uses as much as digits as its factorization.

129556169 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 145800, while the sum is 44.

The square root of 129556169 is about 11382.2743333659. The cubic root of 129556169 is about 506.0025425984.

The spelling of 129556169 in words is "one hundred twenty-nine million, five hundred fifty-six thousand, one hundred sixty-nine".