21729612480 has 448 divisors, whose sum is σ = 74327113728. Its totient is φ = 5366394880.

The previous prime is 21729612479. The next prime is 21729612511. The reversal of 21729612480 is 8421692712.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 130117357 + ... + 130117523.

It is an arithmetic number, because the mean of its divisors is an integer number (165908736).

Almost surely, 2^21729612480 is an apocalyptic number.

21729612480 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 21729612480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37163556864).

21729612480 is an abundant number, since it is smaller than the sum of its proper divisors (52597501248).

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

21729612480 is a wasteful number, since it uses less digits than its factorization.

21729612480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 364 (or 354 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 42.

The spelling of 21729612480 in words is "twenty-one billion, seven hundred twenty-nine million, six hundred twelve thousand, four hundred eighty".