21007008528 has 160 divisors (see below), whose sum is σ = 63748062720. Its totient is φ = 5889607680.

The previous prime is 21007008523. The next prime is 21007008553. The reversal of 21007008528 is 82580070012.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (21007008521) 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, 509751 + ... + 549417.

It is an arithmetic number, because the mean of its divisors is an integer number (398425392).

Almost surely, 2^21007008528 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 21007008528, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31874031360).

21007008528 is an abundant number, since it is smaller than the sum of its proper divisors (42741054192).

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

21007008528 is a wasteful number, since it uses less digits than its factorization.

21007008528 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39765 (or 39759 counting only the distinct ones).

The product of its (nonzero) digits is 8960, while the sum is 33.

The spelling of 21007008528 in words is "twenty-one billion, seven million, eight thousand, five hundred twenty-eight".