21742434560 has 288 divisors, whose sum is σ = 66048998400. Its totient is φ = 6660218880.

The previous prime is 21742434557. The next prime is 21742434587. The reversal of 21742434560 is 6543424712.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5813171 + ... + 5816909.

It is an arithmetic number, because the mean of its divisors is an integer number (229336800).

Almost surely, 2^21742434560 is an apocalyptic number.

21742434560 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 21742434560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33024499200).

21742434560 is an abundant number, since it is smaller than the sum of its proper divisors (44306563840).

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

21742434560 is a wasteful number, since it uses less digits than its factorization.

21742434560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3837 (or 3823 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 38.

The spelling of 21742434560 in words is "twenty-one billion, seven hundred forty-two million, four hundred thirty-four thousand, five hundred sixty".