21818016948 has 432 divisors, whose sum is σ = 67923334080. Its totient is φ = 5424427008.

The previous prime is 21818016947. The next prime is 21818016991. The reversal of 21818016948 is 84961081812.

It is a junction number, because it is equal to n+sod(n) for n = 21818016897 and 21818016906.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21818016947) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 193079740 + ... + 193079852.

It is an arithmetic number, because the mean of its divisors is an integer number (157229940).

Almost surely, 2^21818016948 is an apocalyptic number.

21818016948 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21818016948, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33961667040).

21818016948 is an abundant number, since it is smaller than the sum of its proper divisors (46105317132).

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

21818016948 is a wasteful number, since it uses less digits than its factorization.

21818016948 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 256 (or 234 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 48.

The spelling of 21818016948 in words is "twenty-one billion, eight hundred eighteen million, sixteen thousand, nine hundred forty-eight".