172203928509 has 4 divisors (see below), whose sum is σ = 229605238016. Its totient is φ = 114802619004.

The previous prime is 172203928493. The next prime is 172203928517. The reversal of 172203928509 is 905829302271.

172203928509 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 not a de Polignac number, because 172203928509 - 2⁴ = 172203928493 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172203128509) 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, 28700654749 + ... + 28700654754.

It is an arithmetic number, because the mean of its divisors is an integer number (57401309504).

Almost surely, 2^172203928509 is an apocalyptic number.

It is an amenable number.

172203928509 is a deficient number, since it is larger than the sum of its proper divisors (57401309507).

172203928509 is an equidigital number, since it uses as much as digits as its factorization.

172203928509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57401309506.

The product of its (nonzero) digits is 544320, while the sum is 48.

The spelling of 172203928509 in words is "one hundred seventy-two billion, two hundred three million, nine hundred twenty-eight thousand, five hundred nine".