21573545088 has 128 divisors (see below), whose sum is σ = 61234272000. Its totient is φ = 6705856512.

The previous prime is 21573545033. The next prime is 21573545101. The reversal of 21573545088 is 88054537512.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 696393 + ... + 726711.

It is an arithmetic number, because the mean of its divisors is an integer number (478392750).

Almost surely, 2^21573545088 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21573545088, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30617136000).

21573545088 is an abundant number, since it is smaller than the sum of its proper divisors (39660726912).

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

21573545088 is a wasteful number, since it uses less digits than its factorization.

21573545088 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30462 (or 30450 counting only the distinct ones).

The product of its (nonzero) digits is 1344000, while the sum is 48.

The spelling of 21573545088 in words is "twenty-one billion, five hundred seventy-three million, five hundred forty-five thousand, eighty-eight".