28728716173 has 4 divisors (see below), whose sum is σ = 28760391520. Its totient is φ = 28697040828.

The previous prime is 28728716171. The next prime is 28728716309. The reversal of 28728716173 is 37161782782.

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.

It is a cyclic number.

It is not a de Polignac number, because 28728716173 - 2¹ = 28728716171 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28728716173.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28728716171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15836313 + ... + 15838126.

It is an arithmetic number, because the mean of its divisors is an integer number (7190097880).

Almost surely, 2^28728716173 is an apocalyptic number.

It is an amenable number.

28728716173 is a deficient number, since it is larger than the sum of its proper divisors (31675347).

28728716173 is an equidigital number, since it uses as much as digits as its factorization.

28728716173 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31675346.

The product of its digits is 1580544, while the sum is 52.

The spelling of 28728716173 in words is "twenty-eight billion, seven hundred twenty-eight million, seven hundred sixteen thousand, one hundred seventy-three".