72171144 has 24 divisors (see below), whose sum is σ = 195463710. Its totient is φ = 24057024.

The previous prime is 72171133. The next prime is 72171149. The reversal of 72171144 is 44117127.

It can be written as a sum of positive squares in only one way, i.e., 53144100 + 19027044 = 7290^2 + 4362^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is not an unprimeable number, because it can be changed into a prime (72171149) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 501117 + ... + 501260.

Almost surely, 2^72171144 is an apocalyptic number.

It is an amenable number.

72171144 is an abundant number, since it is smaller than the sum of its proper divisors (123292566).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

72171144 is a wasteful number, since it uses less digits than its factorization.

72171144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1002389 (or 1002382 counting only the distinct ones).

The product of its digits is 1568, while the sum is 27.

The square root of 72171144 is about 8495.3601453970. The cubic root of 72171144 is about 416.3461277325.

The spelling of 72171144 in words is "seventy-two million, one hundred seventy-one thousand, one hundred forty-four".