20863449852 has 144 divisors (see below), whose sum is σ = 62213034240. Its totient is φ = 5314940928.

The previous prime is 20863449839. The next prime is 20863449863. The reversal of 20863449852 is 25894436802.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a junction number, because it is equal to n+sod(n) for n = 20863449795 and 20863449804.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 438628 + ... + 483860.

It is an arithmetic number, because the mean of its divisors is an integer number (432034960).

Almost surely, 2^20863449852 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 20863449852, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31106517120).

20863449852 is an abundant number, since it is smaller than the sum of its proper divisors (41349584388).

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

20863449852 is a wasteful number, since it uses less digits than its factorization.

20863449852 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45300 (or 45281 counting only the distinct ones).

The product of its (nonzero) digits is 3317760, while the sum is 51.

The spelling of 20863449852 in words is "twenty billion, eight hundred sixty-three million, four hundred forty-nine thousand, eight hundred fifty-two".