72073728 has 60 divisors (see below), whose sum is σ = 208022958. Its totient is φ = 24023040.

The previous prime is 72073721. The next prime is 72073739. The reversal of 72073728 is 82737027.

It can be written as a sum of positive squares in only one way, i.e., 38340864 + 33732864 = 6192^2 + 5808^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 72073692 and 72073701.

It is not an unprimeable number, because it can be changed into a prime (72073721) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3213 + ... + 12428.

Almost surely, 2^72073728 is an apocalyptic number.

It is an amenable number.

72073728 is an abundant number, since it is smaller than the sum of its proper divisors (135949230).

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

72073728 is a wasteful number, since it uses less digits than its factorization.

72073728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15665 (or 15646 counting only the distinct ones).

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

The square root of 72073728 is about 8489.6247266885. The cubic root of 72073728 is about 416.1587165575.

The spelling of 72073728 in words is "seventy-two million, seventy-three thousand, seven hundred twenty-eight".