72171624 has 64 divisors (see below), whose sum is σ = 207100800. Its totient is φ = 20530944.

The previous prime is 72171611. The next prime is 72171629. The reversal of 72171624 is 42617127.

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 72171591 and 72171600.

It is not an unprimeable number, because it can be changed into a prime (72171629) 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, 44394 + ... + 45990.

It is an arithmetic number, because the mean of its divisors is an integer number (3235950).

Almost surely, 2^72171624 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 72171624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (103550400).

72171624 is an abundant number, since it is smaller than the sum of its proper divisors (134929176).

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

72171624 is a wasteful number, since it uses less digits than its factorization.

72171624 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1882 (or 1878 counting only the distinct ones).

The product of its digits is 4704, while the sum is 30.

The square root of 72171624 is about 8495.3883960652. The cubic root of 72171624 is about 416.3470507501.

The spelling of 72171624 in words is "seventy-two million, one hundred seventy-one thousand, six hundred twenty-four".