20187278208 has 96 divisors (see below), whose sum is σ = 58183474440. Its totient is φ = 6718381056.

The previous prime is 20187278203. The next prime is 20187278257. The reversal of 20187278208 is 80287278102.

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20187278203) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 727110 + ... + 754362.

Almost surely, 2^20187278208 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 20187278208, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29091737220).

20187278208 is an abundant number, since it is smaller than the sum of its proper divisors (37996196232).

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

20187278208 is a wasteful number, since it uses less digits than its factorization.

20187278208 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27916 (or 27901 counting only the distinct ones).

The product of its (nonzero) digits is 200704, while the sum is 45.

The spelling of 20187278208 in words is "twenty billion, one hundred eighty-seven million, two hundred seventy-eight thousand, two hundred eight".