20686583808 has 288 divisors, whose sum is σ = 65596592880. Its totient is φ = 6228541440.

The previous prime is 20686583803. The next prime is 20686583843. The reversal of 20686583808 is 80838568602.

20686583808 is a `hidden beast` number, since 206 + 8 + 6 + 58 + 380 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20686583803) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 52107066 + ... + 52107462.

Almost surely, 2^20686583808 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 20686583808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32798296440).

20686583808 is an abundant number, since it is smaller than the sum of its proper divisors (44910009072).

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

20686583808 is a wasteful number, since it uses less digits than its factorization.

20686583808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 693 (or 670 counting only the distinct ones).

The product of its (nonzero) digits is 4423680, while the sum is 54.

The spelling of 20686583808 in words is "twenty billion, six hundred eighty-six million, five hundred eighty-three thousand, eight hundred eight".