20805552 has 80 divisors (see below), whose sum is σ = 63254880. Its totient is φ = 6524928.

The previous prime is 20805539. The next prime is 20805553. The reversal of 20805552 is 25550802.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (20805553) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5928 + ... + 8760.

It is an arithmetic number, because the mean of its divisors is an integer number (790686).

Almost surely, 2^20805552 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20805552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31627440).

20805552 is an abundant number, since it is smaller than the sum of its proper divisors (42449328).

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

20805552 is a wasteful number, since it uses less digits than its factorization.

20805552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2867 (or 2855 counting only the distinct ones).

The product of its (nonzero) digits is 4000, while the sum is 27.

The square root of 20805552 is about 4561.3103380498. The cubic root of 20805552 is about 275.0382404122.

The spelling of 20805552 in words is "twenty million, eight hundred five thousand, five hundred fifty-two".