72324640 has 96 divisors (see below), whose sum is σ = 185008320. Its totient is φ = 26625024.

The previous prime is 72324631. The next prime is 72324653. The reversal of 72324640 is 4642327.

It is a super-2 number, since 2×72324640² = 10461707102259200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 72324599 and 72324608.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 112159 + ... + 112801.

It is an arithmetic number, because the mean of its divisors is an integer number (1927170).

Almost surely, 2^72324640 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 72324640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92504160).

72324640 is an abundant number, since it is smaller than the sum of its proper divisors (112683680).

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

72324640 is a wasteful number, since it uses less digits than its factorization.

72324640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 714 (or 706 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 28.

The square root of 72324640 is about 8504.3894548639. The cubic root of 72324640 is about 416.6410850072.

Adding to 72324640 its reverse (4642327), we get a palindrome (76966967).

The spelling of 72324640 in words is "seventy-two million, three hundred twenty-four thousand, six hundred forty".