72118728 has 128 divisors (see below), whose sum is σ = 221184000. Its totient is φ = 21591360.

The previous prime is 72118693. The next prime is 72118729. The reversal of 72118728 is 82781127.

It is a happy number.

It is a super-2 number, since 2×72118728² = 10402221856675968, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

Its product of digits (12544) is a multiple of the sum of its prime factors (392).

It is a junction number, because it is equal to n+sod(n) for n = 72118692 and 72118701.

It is not an unprimeable number, because it can be changed into a prime (72118729) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 301633 + ... + 301871.

It is an arithmetic number, because the mean of its divisors is an integer number (1728000).

Almost surely, 2^72118728 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 72118728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (110592000).

72118728 is an abundant number, since it is smaller than the sum of its proper divisors (149065272).

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

72118728 is a wasteful number, since it uses less digits than its factorization.

72118728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392 (or 382 counting only the distinct ones).

The product of its digits is 12544, while the sum is 36.

The square root of 72118728 is about 8492.2746069590. The cubic root of 72118728 is about 416.2453095811.

The spelling of 72118728 in words is "seventy-two million, one hundred eighteen thousand, seven hundred twenty-eight".