21553102080 has 360 divisors, whose sum is σ = 78779619072. Its totient is φ = 5623934976.

The previous prime is 21553102079. The next prime is 21553102091. The reversal of 21553102080 is 8020135512.

It is a happy number.

21553102080 is a `hidden beast` number, since 2 + 1 + 553 + 10 + 20 + 80 = 666.

It is a tau number, because it is divible by the number of its divisors (360).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 4870749 + ... + 4875171.

Almost surely, 2^21553102080 is an apocalyptic number.

21553102080 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 21553102080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39389809536).

21553102080 is an abundant number, since it is smaller than the sum of its proper divisors (57226516992).

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

21553102080 is an equidigital number, since it uses as much as digits as its factorization.

21553102080 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4503 (or 4480 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 27.

Adding to 21553102080 its reverse (8020135512), we get a palindrome (29573237592).

The spelling of 21553102080 in words is "twenty-one billion, five hundred fifty-three million, one hundred two thousand, eighty".