172729798889 has 2 divisors, whose sum is σ = 172729798890. Its totient is φ = 172729798888.

The previous prime is 172729798849. The next prime is 172729798921. The reversal of 172729798889 is 988897927271.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 108114700864 + 64615098025 = 328808^2 + 254195^2 .

It is an emirp because it is prime and its reverse (988897927271) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 172729798889 - 2²⁸ = 172461363433 is a prime.

It is not a weakly prime, because it can be changed into another prime (172729798849) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86364899444 + 86364899445.

It is an arithmetic number, because the mean of its divisors is an integer number (86364899445).

Almost surely, 2^172729798889 is an apocalyptic number.

It is an amenable number.

172729798889 is a deficient number, since it is larger than the sum of its proper divisors (1).

172729798889 is an equidigital number, since it uses as much as digits as its factorization.

172729798889 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 512096256, while the sum is 77.

The spelling of 172729798889 in words is "one hundred seventy-two billion, seven hundred twenty-nine million, seven hundred ninety-eight thousand, eight hundred eighty-nine".