129173557 has 2 divisors, whose sum is σ = 129173558. Its totient is φ = 129173556.

The previous prime is 129173509. The next prime is 129173563. The reversal of 129173557 is 755371921.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 127825636 + 1347921 = 11306^2 + 1161^2 .

It is a cyclic number.

It is not a de Polignac number, because 129173557 - 2¹¹ = 129171509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (129173507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64586778 + 64586779.

It is an arithmetic number, because the mean of its divisors is an integer number (64586779).

Almost surely, 2^129173557 is an apocalyptic number.

It is an amenable number.

129173557 is a deficient number, since it is larger than the sum of its proper divisors (1).

129173557 is an equidigital number, since it uses as much as digits as its factorization.

129173557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 66150, while the sum is 40.

The square root of 129173557 is about 11365.4545443638. The cubic root of 129173557 is about 505.5039337828.

The spelling of 129173557 in words is "one hundred twenty-nine million, one hundred seventy-three thousand, five hundred fifty-seven".