72216320 has 144 divisors (see below), whose sum is σ = 197793792. Its totient is φ = 25006080.

The previous prime is 72216317. The next prime is 72216337. The reversal of 72216320 is 2361227.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 323729 + ... + 323951.

It is an arithmetic number, because the mean of its divisors is an integer number (1373568).

Almost surely, 2^72216320 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 72216320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98896896).

72216320 is an abundant number, since it is smaller than the sum of its proper divisors (125577472).

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

72216320 is a wasteful number, since it uses less digits than its factorization.

72216320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 278 (or 264 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 23.

The square root of 72216320 is about 8498.0185925897. The cubic root of 72216320 is about 416.4329811409.

Adding to 72216320 its reverse (2361227), we get a palindrome (74577547).

The spelling of 72216320 in words is "seventy-two million, two hundred sixteen thousand, three hundred twenty".