21826459788 has 192 divisors, whose sum is σ = 61646635008. Its totient is φ = 5879427840.

The previous prime is 21826459751. The next prime is 21826459829. The reversal of 21826459788 is 88795462812.

It is a Smith number, since the sum of its digits (60) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 23047531 + ... + 23048477.

It is an arithmetic number, because the mean of its divisors is an integer number (321076224).

Almost surely, 2^21826459788 is an apocalyptic number.

21826459788 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 21826459788, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30823317504).

21826459788 is an abundant number, since it is smaller than the sum of its proper divisors (39820175220).

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

21826459788 is a wasteful number, since it uses less digits than its factorization.

21826459788 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1212 (or 1210 counting only the distinct ones).

The product of its digits is 15482880, while the sum is 60.

The spelling of 21826459788 in words is "twenty-one billion, eight hundred twenty-six million, four hundred fifty-nine thousand, seven hundred eighty-eight".