21552804450 has 144 divisors (see below), whose sum is σ = 58505928000. Its totient is φ = 5688144000.

The previous prime is 21552804431. The next prime is 21552804509. The reversal of 21552804450 is 5440825512.

21552804450 is a `hidden beast` number, since 21 + 552 + 80 + 4 + 4 + 5 + 0 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 20506425 + ... + 20507475.

Almost surely, 2^21552804450 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21552804450, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29252964000).

21552804450 is an abundant number, since it is smaller than the sum of its proper divisors (36953123550).

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

21552804450 is a wasteful number, since it uses less digits than its factorization.

21552804450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1497 (or 1489 counting only the distinct ones).

The product of its (nonzero) digits is 64000, while the sum is 36.

The spelling of 21552804450 in words is "twenty-one billion, five hundred fifty-two million, eight hundred four thousand, four hundred fifty".