21531160000 has 280 divisors, whose sum is σ = 61587985536. Its totient is φ = 7313280000.

The previous prime is 21531159973. The next prime is 21531160009. The reversal of 21531160000 is 6113512.

It is a tau number, because it is divible by the number of its divisors (280).

It is a self number, because there is not a number n which added to its sum of digits gives 21531160000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21531160009) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 36679707 + ... + 36680293.

Almost surely, 2^21531160000 is an apocalyptic number.

21531160000 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 21531160000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30793992768).

21531160000 is an abundant number, since it is smaller than the sum of its proper divisors (40056825536).

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

21531160000 is an equidigital number, since it uses as much as digits as its factorization.

21531160000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 757 (or 732 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 19.

Adding to 21531160000 its reverse (6113512), we get a palindrome (21537273512).

The spelling of 21531160000 in words is "twenty-one billion, five hundred thirty-one million, one hundred sixty thousand".