21601532064 has 96 divisors (see below), whose sum is σ = 67039297920. Its totient is φ = 5959037952.

The previous prime is 21601532063. The next prime is 21601532083. The reversal of 21601532064 is 46023510612.

It is a tau number, because it is divible by the number of its divisors (96).

It is not an unprimeable number, because it can be changed into a prime (21601532063) 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, 534739 + ... + 573714.

It is an arithmetic number, because the mean of its divisors is an integer number (698326020).

Almost surely, 2^21601532064 is an apocalyptic number.

21601532064 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21601532064 is an abundant number, since it is smaller than the sum of its proper divisors (45437765856).

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

21601532064 is a wasteful number, since it uses less digits than its factorization.

21601532064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1108502 (or 1108494 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 30.

The spelling of 21601532064 in words is "twenty-one billion, six hundred one million, five hundred thirty-two thousand, sixty-four".