72042728 has 32 divisors (see below), whose sum is σ = 142732800. Its totient is φ = 34034112.

The previous prime is 72042721. The next prime is 72042731. The reversal of 72042728 is 82724027.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 72042694 and 72042703.

It is not an unprimeable number, because it can be changed into a prime (72042721) 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 7 ways as a sum of consecutive naturals, for example, 7601 + ... + 14207.

It is an arithmetic number, because the mean of its divisors is an integer number (4460400).

Almost surely, 2^72042728 is an apocalyptic number.

It is an amenable number.

72042728 is a deficient number, since it is larger than the sum of its proper divisors (70690072).

72042728 is a wasteful number, since it uses less digits than its factorization.

72042728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6689 (or 6685 counting only the distinct ones).

The product of its (nonzero) digits is 12544, while the sum is 32.

The square root of 72042728 is about 8487.7987723555. The cubic root of 72042728 is about 416.0990426160.

The spelling of 72042728 in words is "seventy-two million, forty-two thousand, seven hundred twenty-eight".