21180710912 has 80 divisors (see below), whose sum is σ = 43033518000. Its totient is φ = 10422845440.

The previous prime is 21180710911. The next prime is 21180710917. The reversal of 21180710912 is 21901708112.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21180710911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37224164 + ... + 37224732.

It is an arithmetic number, because the mean of its divisors is an integer number (537918975).

Almost surely, 2^21180710912 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 21180710912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21516759000).

21180710912 is an abundant number, since it is smaller than the sum of its proper divisors (21852807088).

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

21180710912 is an frugal number, since it uses more digits than its factorization.

21180710912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 678 (or 642 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 32.

The spelling of 21180710912 in words is "twenty-one billion, one hundred eighty million, seven hundred ten thousand, nine hundred twelve".