20005680 has 40 divisors (see below), whose sum is σ = 62018352. Its totient is φ = 5334784.

The previous prime is 20005673. The next prime is 20005681. The reversal of 20005680 is 8650002.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (20005681) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41439 + ... + 41918.

Almost surely, 2^20005680 is an apocalyptic number.

20005680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20005680 is an abundant number, since it is smaller than the sum of its proper divisors (42012672).

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

20005680 is a wasteful number, since it uses less digits than its factorization.

20005680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83373 (or 83367 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 20005680 is about 4472.7709532235. The cubic root of 20005680 is about 271.4674557140.

Adding to 20005680 its reverse (8650002), we get a palindrome (28655682).

The spelling of 20005680 in words is "twenty million, five thousand, six hundred eighty".