173208452561 has 4 divisors (see below), whose sum is σ = 173209481124. Its totient is φ = 173207424000.

The previous prime is 173208452537. The next prime is 173208452579. The reversal of 173208452561 is 165254802371.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 160048003600 + 13160448961 = 400060^2 + 114719^2 .

It is a cyclic number.

It is not a de Polignac number, because 173208452561 - 2¹⁸ = 173208190417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (173208452581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 196040 + ... + 620361.

It is an arithmetic number, because the mean of its divisors is an integer number (43302370281).

Almost surely, 2^173208452561 is an apocalyptic number.

It is an amenable number.

173208452561 is a deficient number, since it is larger than the sum of its proper divisors (1028563).

173208452561 is an equidigital number, since it uses as much as digits as its factorization.

173208452561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1028562.

The product of its (nonzero) digits is 403200, while the sum is 44.

The spelling of 173208452561 in words is "one hundred seventy-three billion, two hundred eight million, four hundred fifty-two thousand, five hundred sixty-one".