21633946880 has 432 divisors, whose sum is σ = 65717502480. Its totient is φ = 6803177472.

The previous prime is 21633946861. The next prime is 21633946889. The reversal of 21633946880 is 8864933612.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 18123621376 + 3510325504 = 134624^2 + 59248^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21633946889) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 137795762 + ... + 137795918.

Almost surely, 2^21633946880 is an apocalyptic number.

21633946880 is a gapful number since it is divisible by the number (20) 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 21633946880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32858751240).

21633946880 is an abundant number, since it is smaller than the sum of its proper divisors (44083555600).

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

21633946880 is an equidigital number, since it uses as much as digits as its factorization.

21633946880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231 (or 184 counting only the distinct ones).

The product of its (nonzero) digits is 1492992, while the sum is 50.

The spelling of 21633946880 in words is "twenty-one billion, six hundred thirty-three million, nine hundred forty-six thousand, eight hundred eighty".