20728675 has 12 divisors (see below), whose sum is σ = 28040616. Its totient is φ = 15075200.

The previous prime is 20728637. The next prime is 20728691. The reversal of 20728675 is 57682702.

It is not a de Polignac number, because 20728675 - 2¹¹ = 20726627 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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, 37414 + ... + 37963.

It is an arithmetic number, because the mean of its divisors is an integer number (2336718).

Almost surely, 2^20728675 is an apocalyptic number.

20728675 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20728675 is a deficient number, since it is larger than the sum of its proper divisors (7311941).

20728675 is a wasteful number, since it uses less digits than its factorization.

20728675 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75398 (or 75393 counting only the distinct ones).

The product of its (nonzero) digits is 47040, while the sum is 37.

The square root of 20728675 is about 4552.8754650221. The cubic root of 20728675 is about 274.6990647431.

It can be divided in two parts, 207 and 28675, that added together give a palindrome (28882).

The spelling of 20728675 in words is "twenty million, seven hundred twenty-eight thousand, six hundred seventy-five".