172722509 has 4 divisors (see below), whose sum is σ = 176397504. Its totient is φ = 169047516.

The previous prime is 172722493. The next prime is 172722523. The reversal of 172722509 is 905227271.

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 172722509 - 2⁴ = 172722493 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172722569) 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, 1837427 + ... + 1837520.

It is an arithmetic number, because the mean of its divisors is an integer number (44099376).

Almost surely, 2^172722509 is an apocalyptic number.

It is an amenable number.

172722509 is a deficient number, since it is larger than the sum of its proper divisors (3674995).

172722509 is an equidigital number, since it uses as much as digits as its factorization.

172722509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3674994.

The product of its (nonzero) digits is 17640, while the sum is 35.

The square root of 172722509 is about 13142.3935795577. The cubic root of 172722509 is about 556.9073880106.

The spelling of 172722509 in words is "one hundred seventy-two million, seven hundred twenty-two thousand, five hundred nine".