72365891 has 4 divisors (see below), whose sum is σ = 77932512. Its totient is φ = 66799272.

The previous prime is 72365869. The next prime is 72365893. The reversal of 72365891 is 19856327.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72365891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72365893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2783291 + ... + 2783316.

It is an arithmetic number, because the mean of its divisors is an integer number (19483128).

Almost surely, 2^72365891 is an apocalyptic number.

72365891 is a deficient number, since it is larger than the sum of its proper divisors (5566621).

72365891 is a wasteful number, since it uses less digits than its factorization.

72365891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5566620.

The product of its digits is 90720, while the sum is 41.

The square root of 72365891 is about 8506.8143861260. The cubic root of 72365891 is about 416.7202815985.

The spelling of 72365891 in words is "seventy-two million, three hundred sixty-five thousand, eight hundred ninety-one".