173628561 has 4 divisors (see below), whose sum is σ = 231504752. Its totient is φ = 115752372.

The previous prime is 173628503. The next prime is 173628569. The reversal of 173628561 is 165826371.

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: 165826371 = 3 ⋅55275457.

It is not a de Polignac number, because 173628561 - 2¹⁹ = 173104273 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (173628569) 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, 28938091 + ... + 28938096.

It is an arithmetic number, because the mean of its divisors is an integer number (57876188).

Almost surely, 2^173628561 is an apocalyptic number.

It is an amenable number.

173628561 is a deficient number, since it is larger than the sum of its proper divisors (57876191).

173628561 is an equidigital number, since it uses as much as digits as its factorization.

173628561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57876190.

The product of its digits is 60480, while the sum is 39.

The square root of 173628561 is about 13176.8190774557. The cubic root of 173628561 is about 557.8794815579.

The spelling of 173628561 in words is "one hundred seventy-three million, six hundred twenty-eight thousand, five hundred sixty-one".