20565583280 has 80 divisors (see below), whose sum is σ = 54907200000. Its totient is φ = 7084788480.

The previous prime is 20565583183. The next prime is 20565583289. The reversal of 20565583280 is 8238556502.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (44).

It is not an unprimeable number, because it can be changed into a prime (20565583289) 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, 598280 + ... + 631719.

It is an arithmetic number, because the mean of its divisors is an integer number (686340000).

Almost surely, 2^20565583280 is an apocalyptic number.

20565583280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20565583280 is an abundant number, since it is smaller than the sum of its proper divisors (34341616720).

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

20565583280 is a wasteful number, since it uses less digits than its factorization.

20565583280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1230042 (or 1230036 counting only the distinct ones).

The product of its (nonzero) digits is 576000, while the sum is 44.

The spelling of 20565583280 in words is "twenty billion, five hundred sixty-five million, five hundred eighty-three thousand, two hundred eighty".