72171543 has 4 divisors (see below), whose sum is σ = 96228728. Its totient is φ = 48114360.

The previous prime is 72171527. The next prime is 72171553. The reversal of 72171543 is 34517127.

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

It is not a de Polignac number, because 72171543 - 2⁴ = 72171527 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 72171543.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72171553) 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, 12028588 + ... + 12028593.

It is an arithmetic number, because the mean of its divisors is an integer number (24057182).

Almost surely, 2^72171543 is an apocalyptic number.

72171543 is a deficient number, since it is larger than the sum of its proper divisors (24057185).

72171543 is a wasteful number, since it uses less digits than its factorization.

72171543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24057184.

The product of its digits is 5880, while the sum is 30.

The square root of 72171543 is about 8495.3836287716. The cubic root of 72171543 is about 416.3468949911.

The spelling of 72171543 in words is "seventy-two million, one hundred seventy-one thousand, five hundred forty-three".