20805200 has 60 divisors (see below), whose sum is σ = 53842908. Its totient is φ = 7680000.

The previous prime is 20805199. The next prime is 20805223. The reversal of 20805200 is 250802.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 7203856 + 13601344 = 2684^2 + 3688^2 .

It is a congruent 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, 3200 + ... + 7200.

Almost surely, 2^20805200 is an apocalyptic number.

20805200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20805200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26921454).

20805200 is an abundant number, since it is smaller than the sum of its proper divisors (33037708).

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

20805200 is a wasteful number, since it uses less digits than its factorization.

20805200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4032 (or 4021 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 17.

The square root of 20805200 is about 4561.2717524831. The cubic root of 20805200 is about 275.0366893197.

The spelling of 20805200 in words is "twenty million, eight hundred five thousand, two hundred".