72021240720 has 400 divisors, whose sum is σ = 293875065792. Its totient is φ = 16116433920.

The previous prime is 72021240701. The next prime is 72021240721. The reversal of 72021240720 is 2704212027.

72021240720 is a `hidden beast` number, since 7 + 20 + 212 + 407 + 20 = 666.

It is a super-2 number, since 2×72021240720² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (72021240721) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 887779 + ... + 965501.

Almost surely, 2^72021240720 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 72021240720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (146937532896).

72021240720 is an abundant number, since it is smaller than the sum of its proper divisors (221853825072).

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

72021240720 is a wasteful number, since it uses less digits than its factorization.

72021240720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77772 (or 77757 counting only the distinct ones).

The product of its (nonzero) digits is 3136, while the sum is 27.

Adding to 72021240720 its reverse (2704212027), we get a palindrome (74725452747).

The spelling of 72021240720 in words is "seventy-two billion, twenty-one million, two hundred forty thousand, seven hundred twenty".