728730144 has 108 divisors (see below), whose sum is σ = 2142145278. Its totient is φ = 234984960.

The previous prime is 728730097. The next prime is 728730169. The reversal of 728730144 is 441037827.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 697593744 + 31136400 = 26412^2 + 5580^2 .

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 = 728730099 and 728730108.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 275452 + ... + 278084.

Almost surely, 2^728730144 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 728730144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1071072639).

728730144 is an abundant number, since it is smaller than the sum of its proper divisors (1413415134).

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

728730144 is a wasteful number, since it uses less digits than its factorization.

728730144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2711 (or 2669 counting only the distinct ones).

The product of its (nonzero) digits is 37632, while the sum is 36.

The square root of 728730144 is about 26995.0022041118. The cubic root of 728730144 is about 899.8889344425. Note that the first 3 decimals are identical.

The spelling of 728730144 in words is "seven hundred twenty-eight million, seven hundred thirty thousand, one hundred forty-four".