20563660 has 48 divisors (see below), whose sum is σ = 46922400. Its totient is φ = 7524864.

The previous prime is 20563657. The next prime is 20563661. The reversal of 20563660 is 6636502.

It is a super-2 number, since 2×20563660² = 845728225191200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20563661) 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 15 ways as a sum of consecutive naturals, for example, 35856 + ... + 36424.

It is an arithmetic number, because the mean of its divisors is an integer number (977550).

Almost surely, 2^20563660 is an apocalyptic number.

20563660 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 20563660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23461200).

20563660 is an abundant number, since it is smaller than the sum of its proper divisors (26358740).

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

20563660 is a wasteful number, since it uses less digits than its factorization.

20563660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 730 (or 728 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 28.

The square root of 20563660 is about 4534.7171907408. The cubic root of 20563660 is about 273.9681885387.

The spelling of 20563660 in words is "twenty million, five hundred sixty-three thousand, six hundred sixty".