55801728 has 96 divisors (see below), whose sum is σ = 163495800. Its totient is φ = 18263040.

The previous prime is 55801723. The next prime is 55801747. The reversal of 55801728 is 82710855.

55801728 is a `hidden beast` number, since 5 + 580 + 1 + 72 + 8 = 666.

55801728 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×55801728² = 6227665695571968, which contains 22 as substring.

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 = 55801692 and 55801701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55801721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 67558 + ... + 68378.

Almost surely, 2^55801728 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 55801728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (81747900).

55801728 is an abundant number, since it is smaller than the sum of its proper divisors (107694072).

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

55801728 is a wasteful number, since it uses less digits than its factorization.

55801728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 900 (or 885 counting only the distinct ones).

The product of its (nonzero) digits is 22400, while the sum is 36.

The square root of 55801728 is about 7470.0554214812. The cubic root of 55801728 is about 382.1341779860.

The spelling of 55801728 in words is "fifty-five million, eight hundred one thousand, seven hundred twenty-eight".