21711647480 has 64 divisors (see below), whose sum is σ = 49858416000. Its totient is φ = 8507055744.

The previous prime is 21711647443. The next prime is 21711647483. The reversal of 21711647480 is 8474611712.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21711647483) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 457091 + ... + 502349.

It is an arithmetic number, because the mean of its divisors is an integer number (779037750).

Almost surely, 2^21711647480 is an apocalyptic number.

21711647480 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 21711647480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24929208000).

21711647480 is an abundant number, since it is smaller than the sum of its proper divisors (28146768520).

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

21711647480 is a wasteful number, since it uses less digits than its factorization.

21711647480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45516 (or 45512 counting only the distinct ones).

The product of its (nonzero) digits is 75264, while the sum is 41.

The spelling of 21711647480 in words is "twenty-one billion, seven hundred eleven million, six hundred forty-seven thousand, four hundred eighty".