728100 has 54 divisors (see below), whose sum is σ = 2285010. Its totient is φ = 193920.

The previous prime is 728087. The next prime is 728113. The reversal of 728100 is 1827.

It is an interprime number because it is at equal distance from previous prime (728087) and next prime (728113).

It can be written as a sum of positive squares in 3 ways, for example, as 147456 + 580644 = 384^2 + 762^2 .

It is a super-2 number, since 2×728100² = 1060259220000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

728100 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 496 + ... + 1304.

It is an arithmetic number, because the mean of its divisors is an integer number (42315).

2⁷²⁸¹⁰⁰ 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 728100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1142505).

728100 is an abundant number, since it is smaller than the sum of its proper divisors (1556910).

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

728100 is a wasteful number, since it uses less digits than its factorization.

728100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 829 (or 819 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 18.

The square root of 728100 is about 853.2877591997. The cubic root of 728100 is about 89.9629477109.

Adding to 728100 its reverse (1827), we get a palindrome (729927).

It can be divided in two parts, 728 and 100, that added together give a palindrome (828).

The spelling of 728100 in words is "seven hundred twenty-eight thousand, one hundred".