72328591 has 4 divisors (see below), whose sum is σ = 76583232. Its totient is φ = 68073952.

The previous prime is 72328589. The next prime is 72328601. The reversal of 72328591 is 19582327.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 72328591 - 2¹ = 72328589 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 72328591.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72328541) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2127295 + ... + 2127328.

It is an arithmetic number, because the mean of its divisors is an integer number (19145808).

Almost surely, 2^72328591 is an apocalyptic number.

72328591 is a deficient number, since it is larger than the sum of its proper divisors (4254641).

72328591 is a wasteful number, since it uses less digits than its factorization.

72328591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4254640.

The product of its digits is 30240, while the sum is 37.

The square root of 72328591 is about 8504.6217434992. The cubic root of 72328591 is about 416.6486717206.

The spelling of 72328591 in words is "seventy-two million, three hundred twenty-eight thousand, five hundred ninety-one".