20789556 has 12 divisors (see below), whose sum is σ = 48508992. Its totient is φ = 6929848.

The previous prime is 20789551. The next prime is 20789563. The reversal of 20789556 is 65598702.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20789551) 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 3 ways as a sum of consecutive naturals, for example, 866220 + ... + 866243.

It is an arithmetic number, because the mean of its divisors is an integer number (4042416).

Almost surely, 2^20789556 is an apocalyptic number.

It is an amenable number.

20789556 is an abundant number, since it is smaller than the sum of its proper divisors (27719436).

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

20789556 is a wasteful number, since it uses less digits than its factorization.

20789556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1732470 (or 1732468 counting only the distinct ones).

The product of its (nonzero) digits is 151200, while the sum is 42.

The square root of 20789556 is about 4559.5565573858. The cubic root of 20789556 is about 274.9677361598.

The spelling of 20789556 in words is "twenty million, seven hundred eighty-nine thousand, five hundred fifty-six".