172161573 has 4 divisors (see below), whose sum is σ = 229548768. Its totient is φ = 114774380.

The previous prime is 172161559. The next prime is 172161599. The reversal of 172161573 is 375161271.

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: 375161271 = 3 ⋅125053757.

It is a cyclic number.

It is not a de Polignac number, because 172161573 - 2⁵ = 172161541 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172161503) 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 in 3 ways as a sum of consecutive naturals, for example, 28693593 + ... + 28693598.

It is an arithmetic number, because the mean of its divisors is an integer number (57387192).

Almost surely, 2^172161573 is an apocalyptic number.

It is an amenable number.

172161573 is a deficient number, since it is larger than the sum of its proper divisors (57387195).

172161573 is an equidigital number, since it uses as much as digits as its factorization.

172161573 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57387194.

The product of its digits is 8820, while the sum is 33.

The square root of 172161573 is about 13121.0355155376. The cubic root of 172161573 is about 556.3038608284.

The spelling of 172161573 in words is "one hundred seventy-two million, one hundred sixty-one thousand, five hundred seventy-three".