72505728 has 48 divisors (see below), whose sum is σ = 208646100. Its totient is φ = 24168192.

The previous prime is 72505723. The next prime is 72505733. The reversal of 72505728 is 82750527.

It is an interprime number because it is at equal distance from previous prime (72505723) and next prime (72505733).

It is a tau number, because it is divible by the number of its divisors (48).

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 = 72505692 and 72505701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72505721) 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, 30318 + ... + 32621.

Almost surely, 2^72505728 is an apocalyptic number.

It is an amenable number.

72505728 is an abundant number, since it is smaller than the sum of its proper divisors (136140372).

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

72505728 is a wasteful number, since it uses less digits than its factorization.

72505728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62959 (or 62944 counting only the distinct ones).

The product of its (nonzero) digits is 39200, while the sum is 36.

The square root of 72505728 is about 8515.0295360615. The cubic root of 72505728 is about 416.9885268482.

The spelling of 72505728 in words is "seventy-two million, five hundred five thousand, seven hundred twenty-eight".