72165191 has 12 divisors (see below), whose sum is σ = 87598512. Its totient is φ = 59165568.

The previous prime is 72165131. The next prime is 72165229. The reversal of 72165191 is 19156127.

It is not a de Polignac number, because 72165191 - 2⁶ = 72165127 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 (72165101) 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 11 ways as a sum of consecutive naturals, for example, 30890 + ... + 33143.

It is an arithmetic number, because the mean of its divisors is an integer number (7299876).

Almost surely, 2^72165191 is an apocalyptic number.

72165191 is a deficient number, since it is larger than the sum of its proper divisors (15433321).

72165191 is a wasteful number, since it uses less digits than its factorization.

72165191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64070 (or 64063 counting only the distinct ones).

The product of its digits is 3780, while the sum is 32.

The square root of 72165191 is about 8495.0097704476. The cubic root of 72165191 is about 416.3346800518.

The spelling of 72165191 in words is "seventy-two million, one hundred sixty-five thousand, one hundred ninety-one".