72168509 has 8 divisors (see below), whose sum is σ = 82576128. Its totient is φ = 61785360.

The previous prime is 72168497. The next prime is 72168511. The reversal of 72168509 is 90586127.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 72168509 - 2⁴ = 72168493 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 (72168529) 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 7 ways as a sum of consecutive naturals, for example, 719 + ... + 12035.

It is an arithmetic number, because the mean of its divisors is an integer number (10322016).

Almost surely, 2^72168509 is an apocalyptic number.

It is an amenable number.

72168509 is a deficient number, since it is larger than the sum of its proper divisors (10407619).

72168509 is a wasteful number, since it uses less digits than its factorization.

72168509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12235.

The product of its (nonzero) digits is 30240, while the sum is 38.

The square root of 72168509 is about 8495.2050593261. The cubic root of 72168509 is about 416.3410606778.

The spelling of 72168509 in words is "seventy-two million, one hundred sixty-eight thousand, five hundred nine".