20765600 has 72 divisors (see below), whose sum is σ = 51395148. Its totient is φ = 8192000.

The previous prime is 20765599. The next prime is 20765609. The reversal of 20765600 is 656702.

It can be written as a sum of positive squares in 6 ways, for example, as 18905104 + 1860496 = 4348^2 + 1364^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20765600.

It is not an unprimeable number, because it can be changed into a prime (20765609) 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 11 ways as a sum of consecutive naturals, for example, 80672 + ... + 80928.

Almost surely, 2^20765600 is an apocalyptic number.

20765600 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 20765600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25697574).

20765600 is an abundant number, since it is smaller than the sum of its proper divisors (30629548).

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

20765600 is a wasteful number, since it uses less digits than its factorization.

20765600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 378 (or 365 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 26.

The square root of 20765600 is about 4556.9287903148. The cubic root of 20765600 is about 274.8620796009.

The spelling of 20765600 in words is "twenty million, seven hundred sixty-five thousand, six hundred".