1099728 has 60 divisors (see below), whose sum is σ = 3520608. Its totient is φ = 313920.

The previous prime is 1099727. The next prime is 1099729. The reversal of 1099728 is 8279901.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1099727) and next prime (1099729).

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 = 1099692 and 1099701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1099723) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 463 + ... + 1553.

2^1099728 is an apocalyptic number.

1099728 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1099728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1760304).

1099728 is an abundant number, since it is smaller than the sum of its proper divisors (2420880).

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

1099728 is a wasteful number, since it uses less digits than its factorization.

1099728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1112 (or 1103 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The square root of 1099728 is about 1048.6791692410. The cubic root of 1099728 is about 103.2195023536.

It can be divided in two parts, 10997 and 28, that added together give a square (11025 = 105²).

The spelling of 1099728 in words is "one million, ninety-nine thousand, seven hundred twenty-eight".