171099649909 has 4 divisors (see below), whose sum is σ = 171370806880. Its totient is φ = 170828492940.

The previous prime is 171099649891. The next prime is 171099649921. The reversal of 171099649909 is 909946990171.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 909946990171 = 2003 ⋅454292057.

It is a cyclic number.

It is not a de Polignac number, because 171099649909 - 2¹¹ = 171099647861 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (171099649939) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 135577539 + ... + 135578800.

It is an arithmetic number, because the mean of its divisors is an integer number (42842701720).

Almost surely, 2^171099649909 is an apocalyptic number.

It is an amenable number.

171099649909 is a deficient number, since it is larger than the sum of its proper divisors (271156971).

171099649909 is an equidigital number, since it uses as much as digits as its factorization.

171099649909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271156970.

The product of its (nonzero) digits is 9920232, while the sum is 64.

The spelling of 171099649909 in words is "one hundred seventy-one billion, ninety-nine million, six hundred forty-nine thousand, nine hundred nine".