21868186368 has 576 divisors, whose sum is σ = 75161640960. Its totient is φ = 5499518976.

The previous prime is 21868186321. The next prime is 21868186391. The reversal of 21868186368 is 86368186812.

It is a happy number.

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 98063505 + ... + 98063727.

It is an arithmetic number, because the mean of its divisors is an integer number (130488960).

Almost surely, 2^21868186368 is an apocalyptic number.

21868186368 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 21868186368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37580820480).

21868186368 is an abundant number, since it is smaller than the sum of its proper divisors (53293454592).

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

21868186368 is a wasteful number, since it uses less digits than its factorization.

21868186368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 332 (or 318 counting only the distinct ones).

The product of its digits is 5308416, while the sum is 57.

The spelling of 21868186368 in words is "twenty-one billion, eight hundred sixty-eight million, one hundred eighty-six thousand, three hundred sixty-eight".