21201532520 has 64 divisors (see below), whose sum is σ = 54601430400. Its totient is φ = 7258003200.

The previous prime is 21201532519. The next prime is 21201532553. The reversal of 21201532520 is 2523510212.

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, 127070 + ... + 241970.

It is an arithmetic number, because the mean of its divisors is an integer number (853147350).

Almost surely, 2^21201532520 is an apocalyptic number.

21201532520 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 21201532520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27300715200).

21201532520 is an abundant number, since it is smaller than the sum of its proper divisors (33399897880).

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

21201532520 is a wasteful number, since it uses less digits than its factorization.

21201532520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115578 (or 115574 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 23.

The spelling of 21201532520 in words is "twenty-one billion, two hundred one million, five hundred thirty-two thousand, five hundred twenty".