21419565648 has 240 divisors, whose sum is σ = 62787856320. Its totient is φ = 6280974336.

The previous prime is 21419565631. The next prime is 21419565683. The reversal of 21419565648 is 84656591412.

It is a super-3 number, since 3×21419565648³ (a number of 32 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21419565648.

It is a congruent number.

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, 19525036 + ... + 19526132.

It is an arithmetic number, because the mean of its divisors is an integer number (261616068).

Almost surely, 2^21419565648 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 21419565648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31393928160).

21419565648 is an abundant number, since it is smaller than the sum of its proper divisors (41368290672).

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

21419565648 is a wasteful number, since it uses less digits than its factorization.

21419565648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1246 (or 1227 counting only the distinct ones).

The product of its digits is 2073600, while the sum is 51.

The spelling of 21419565648 in words is "twenty-one billion, four hundred nineteen million, five hundred sixty-five thousand, six hundred forty-eight".