20805628 has 12 divisors (see below), whose sum is σ = 36475992. Its totient is φ = 10383920.

The previous prime is 20805623. The next prime is 20805643. The reversal of 20805628 is 82650802.

It is a self number, because there is not a number n which added to its sum of digits gives 20805628.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20805623) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2083 + ... + 6778.

It is an arithmetic number, because the mean of its divisors is an integer number (3039666).

Almost surely, 2^20805628 is an apocalyptic number.

It is an amenable number.

20805628 is a deficient number, since it is larger than the sum of its proper divisors (15670364).

20805628 is a wasteful number, since it uses less digits than its factorization.

20805628 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9452 (or 9450 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 31.

The square root of 20805628 is about 4561.3186689816. The cubic root of 20805628 is about 275.0385753049.

The spelling of 20805628 in words is "twenty million, eight hundred five thousand, six hundred twenty-eight".