72171165 has 16 divisors (see below), whose sum is σ = 125971776. Its totient is φ = 34992000.

The previous prime is 72171149. The next prime is 72171167. The reversal of 72171165 is 56117127.

It is not a de Polignac number, because 72171165 - 2⁴ = 72171149 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72171167) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 218536 + ... + 218865.

It is an arithmetic number, because the mean of its divisors is an integer number (7873236).

Almost surely, 2^72171165 is an apocalyptic number.

It is an amenable number.

72171165 is a deficient number, since it is larger than the sum of its proper divisors (53800611).

72171165 is a wasteful number, since it uses less digits than its factorization.

72171165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 437420.

The product of its digits is 2940, while the sum is 30.

The square root of 72171165 is about 8495.3613813657. The cubic root of 72171165 is about 416.3461681146.

Adding to 72171165 its product of digits (2940), we get a triangular number (72174105 = T₁₂₀₁₄).

The spelling of 72171165 in words is "seventy-two million, one hundred seventy-one thousand, one hundred sixty-five".