21552503500 has 96 divisors (see below), whose sum is σ = 52000865280. Its totient is φ = 7737912000.

The previous prime is 21552503459. The next prime is 21552503509. The reversal of 21552503500 is 530525512.

It is not an unprimeable number, because it can be changed into a prime (21552503509) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 409699 + ... + 459301.

It is an arithmetic number, because the mean of its divisors is an integer number (541675680).

Almost surely, 2^21552503500 is an apocalyptic number.

21552503500 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 21552503500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26000432640).

21552503500 is an abundant number, since it is smaller than the sum of its proper divisors (30448361780).

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

21552503500 is a wasteful number, since it uses less digits than its factorization.

21552503500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49712 (or 49700 counting only the distinct ones).

The product of its (nonzero) digits is 7500, while the sum is 28.

The spelling of 21552503500 in words is "twenty-one billion, five hundred fifty-two million, five hundred three thousand, five hundred".