172028128417 has 4 divisors (see below), whose sum is σ = 172378491696. Its totient is φ = 171677765140.

The previous prime is 172028128381. The next prime is 172028128421. The reversal of 172028128417 is 714821820271.

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 a de Polignac number, because none of the positive numbers 2^k-172028128417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (172028129417) 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, 175180903 + ... + 175181884.

It is an arithmetic number, because the mean of its divisors is an integer number (43094622924).

Almost surely, 2^172028128417 is an apocalyptic number.

It is an amenable number.

172028128417 is a deficient number, since it is larger than the sum of its proper divisors (350363279).

172028128417 is an equidigital number, since it uses as much as digits as its factorization.

172028128417 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 350363278.

The product of its (nonzero) digits is 100352, while the sum is 43.

Adding to 172028128417 its reverse (714821820271), we get a palindrome (886849948688).

The spelling of 172028128417 in words is "one hundred seventy-two billion, twenty-eight million, one hundred twenty-eight thousand, four hundred seventeen".