171728639129 has 2 divisors, whose sum is σ = 171728639130. Its totient is φ = 171728639128.

The previous prime is 171728639111. The next prime is 171728639149. The reversal of 171728639129 is 921936827171.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 143788848025 + 27939791104 = 379195^2 + 167152^2 .

It is a cyclic number.

It is not a de Polignac number, because 171728639129 - 2¹² = 171728635033 is a prime.

It is not a weakly prime, because it can be changed into another prime (171728639149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 85864319564 + 85864319565.

It is an arithmetic number, because the mean of its divisors is an integer number (85864319565).

Almost surely, 2^171728639129 is an apocalyptic number.

It is an amenable number.

171728639129 is a deficient number, since it is larger than the sum of its proper divisors (1).

171728639129 is an equidigital number, since it uses as much as digits as its factorization.

171728639129 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2286144, while the sum is 56.

The spelling of 171728639129 in words is "one hundred seventy-one billion, seven hundred twenty-eight million, six hundred thirty-nine thousand, one hundred twenty-nine".