20636771904 has 336 divisors, whose sum is σ = 71065591168. Its totient is φ = 5601705984.

The previous prime is 20636771879. The next prime is 20636771917. The reversal of 20636771904 is 40917763602.

20636771904 is a `hidden beast` number, since 2 + 0 + 636 + 7 + 7 + 1 + 9 + 0 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (336).

It is a self number, because there is not a number n which added to its sum of digits gives 20636771904.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6413304 + ... + 6416520.

Almost surely, 2^20636771904 is an apocalyptic number.

20636771904 is a gapful number since it is divisible by the number (24) 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 20636771904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35532795584).

20636771904 is an abundant number, since it is smaller than the sum of its proper divisors (50428819264).

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

20636771904 is a wasteful number, since it uses less digits than its factorization.

20636771904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3322 (or 3309 counting only the distinct ones).

The product of its (nonzero) digits is 381024, while the sum is 45.

The spelling of 20636771904 in words is "twenty billion, six hundred thirty-six million, seven hundred seventy-one thousand, nine hundred four".