20928605 has 8 divisors (see below), whose sum is σ = 25170912. Its totient is φ = 16705168.

The previous prime is 20928541. The next prime is 20928629. The reversal of 20928605 is 50682902.

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

It is a cyclic number.

It is not a de Polignac number, because 20928605 - 2⁶ = 20928541 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2147 + ... + 6816.

It is an arithmetic number, because the mean of its divisors is an integer number (3146364).

Almost surely, 2^20928605 is an apocalyptic number.

It is an amenable number.

20928605 is a deficient number, since it is larger than the sum of its proper divisors (4242307).

20928605 is an equidigital number, since it uses as much as digits as its factorization.

20928605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9435.

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 20928605 is about 4574.7792296460. The cubic root of 20928605 is about 275.5794064714.

The spelling of 20928605 in words is "twenty million, nine hundred twenty-eight thousand, six hundred five".