7273728 has 216 divisors, whose sum is σ = 26784576. Its totient is φ = 1843200.

The previous prime is 7273723. The next prime is 7273759. The reversal of 7273728 is 8273727.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

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

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 = 7273692 and 7273701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7273723) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 177388 + ... + 177428.

Almost surely, 2^7273728 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 7273728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13392288).

7273728 is an abundant number, since it is smaller than the sum of its proper divisors (19510848).

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

7273728 is a wasteful number, since it uses less digits than its factorization.

7273728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81 (or 64 counting only the distinct ones).

The product of its digits is 32928, while the sum is 36.

The square root of 7273728 is about 2696.9849832730. The cubic root of 7273728 is about 193.7547472996.

Subtracting 7273728 from its reverse (8273727), we obtain a palindrome (999999).

It can be divided in two parts, 7273 and 728, that added together give a triangular number (8001 = T₁₂₆).

The spelling of 7273728 in words is "seven million, two hundred seventy-three thousand, seven hundred twenty-eight".