21448618208 has 72 divisors (see below), whose sum is σ = 46070107272. Its totient is φ = 9820514304.

The previous prime is 21448618069. The next prime is 21448618211. The reversal of 21448618208 is 80281684412.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 310835 + ... + 373517.

It is an arithmetic number, because the mean of its divisors is an integer number (639862601).

Almost surely, 2^21448618208 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 21448618208, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23035053636).

21448618208 is an abundant number, since it is smaller than the sum of its proper divisors (24621489064).

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

21448618208 is a wasteful number, since it uses less digits than its factorization.

21448618208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62764 (or 62739 counting only the distinct ones).

The product of its (nonzero) digits is 196608, while the sum is 44.

The spelling of 21448618208 in words is "twenty-one billion, four hundred forty-eight million, six hundred eighteen thousand, two hundred eight".