20566144 has 64 divisors (see below), whose sum is σ = 43476480. Its totient is φ = 9676800.

The previous prime is 20566129. The next prime is 20566159. The reversal of 20566144 is 44166502.

It is an interprime number because it is at equal distance from previous prime (20566129) and next prime (20566159).

It is a tau number, because it is divible by the number of its divisors (64).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 281692 + ... + 281764.

It is an arithmetic number, because the mean of its divisors is an integer number (679320).

Almost surely, 2^20566144 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 20566144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21738240).

20566144 is an abundant number, since it is smaller than the sum of its proper divisors (22910336).

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

20566144 is an equidigital number, since it uses as much as digits as its factorization.

20566144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 189 (or 177 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 28.

The square root of 20566144 is about 4534.9910694510. The cubic root of 20566144 is about 273.9792194800.

The spelling of 20566144 in words is "twenty million, five hundred sixty-six thousand, one hundred forty-four".