20895455568 has 160 divisors (see below), whose sum is σ = 58872481920. Its totient is φ = 6347980800.

The previous prime is 20895455551. The next prime is 20895455573. The reversal of 20895455568 is 86555459802.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 28274943 + ... + 28275681.

It is an arithmetic number, because the mean of its divisors is an integer number (367953012).

Almost surely, 2^20895455568 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 20895455568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29436240960).

20895455568 is an abundant number, since it is smaller than the sum of its proper divisors (37977026352).

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

20895455568 is a wasteful number, since it uses less digits than its factorization.

20895455568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1277 (or 1271 counting only the distinct ones).

The product of its (nonzero) digits is 17280000, while the sum is 57.

The spelling of 20895455568 in words is "twenty billion, eight hundred ninety-five million, four hundred fifty-five thousand, five hundred sixty-eight".