21816035648 has 112 divisors (see below), whose sum is σ = 48024434304. Its totient is φ = 9750282240.

The previous prime is 21816035623. The next prime is 21816035663. The reversal of 21816035648 is 84653061812.

It is a super-3 number, since 3×21816035648³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a junction number, because it is equal to n+sod(n) for n = 21816035599 and 21816035608.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11403140 + ... + 11405052.

It is an arithmetic number, because the mean of its divisors is an integer number (428789592).

Almost surely, 2^21816035648 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 21816035648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24012217152).

21816035648 is an abundant number, since it is smaller than the sum of its proper divisors (26208398656).

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

21816035648 is a wasteful number, since it uses less digits than its factorization.

21816035648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2200 (or 2190 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 44.

The spelling of 21816035648 in words is "twenty-one billion, eight hundred sixteen million, thirty-five thousand, six hundred forty-eight".