20728113 has 8 divisors (see below), whose sum is σ = 31585728. Its totient is φ = 11844624.

The previous prime is 20728109. The next prime is 20728121. The reversal of 20728113 is 31182702.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20728113 - 2² = 20728109 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20728133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 493506 + ... + 493547.

It is an arithmetic number, because the mean of its divisors is an integer number (3948216).

Almost surely, 2^20728113 is an apocalyptic number.

It is an amenable number.

20728113 is a deficient number, since it is larger than the sum of its proper divisors (10857615).

20728113 is an equidigital number, since it uses as much as digits as its factorization.

20728113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 987063.

The product of its (nonzero) digits is 672, while the sum is 24.

The square root of 20728113 is about 4552.8137453667. The cubic root of 20728113 is about 274.6965821552.

The spelling of 20728113 in words is "twenty million, seven hundred twenty-eight thousand, one hundred thirteen".