72172144 has 40 divisors (see below), whose sum is σ = 153851760. Its totient is φ = 32795840.

The previous prime is 72172141. The next prime is 72172169. The reversal of 72172144 is 44127127.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72172141) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19602 + ... + 22990.

It is an arithmetic number, because the mean of its divisors is an integer number (3846294).

Almost surely, 2^72172144 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 72172144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (76925880).

72172144 is an abundant number, since it is smaller than the sum of its proper divisors (81679616).

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

72172144 is a wasteful number, since it uses less digits than its factorization.

72172144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3430 (or 3402 counting only the distinct ones).

The product of its digits is 3136, while the sum is 28.

The square root of 72172144 is about 8495.4190008498. The cubic root of 72172144 is about 416.3480506811.

The spelling of 72172144 in words is "seventy-two million, one hundred seventy-two thousand, one hundred forty-four".