72171632 has 40 divisors (see below), whose sum is σ = 153167280. Its totient is φ = 32739840.

The previous prime is 72171629. The next prime is 72171641. The reversal of 72171632 is 23617127.

It is a junction number, because it is equal to n+sod(n) for n = 72171595 and 72171604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9332 + ... + 15212.

It is an arithmetic number, because the mean of its divisors is an integer number (3829182).

Almost surely, 2^72171632 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 72171632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (76583640).

72171632 is an abundant number, since it is smaller than the sum of its proper divisors (80995648).

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

72171632 is a wasteful number, since it uses less digits than its factorization.

72171632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5961 (or 5955 counting only the distinct ones).

The product of its digits is 3528, while the sum is 29.

The square root of 72171632 is about 8495.3888669089. The cubic root of 72171632 is about 416.3470661337.

Adding to 72171632 its reverse (23617127), we get a palindrome (95788759).

The spelling of 72171632 in words is "seventy-two million, one hundred seventy-one thousand, six hundred thirty-two".