21604006217608 has 16 divisors (see below), whose sum is σ = 40765521288780. Its totient is φ = 10733200540608.

The previous prime is 21604006217587. The next prime is 21604006217609. The reversal of 21604006217608 is 80671260040612.

It can be written as a sum of positive squares in 2 ways, for example, as 20810584907044 + 793421310564 = 4561862^2 + 890742^2 .

It is not an unprimeable number, because it can be changed into a prime (21604006217609) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8600319691 + ... + 8600322202.

Almost surely, 2^{21604006217608} is an apocalyptic number.

It is an amenable number.

21604006217608 is a deficient number, since it is larger than the sum of its proper divisors (19161515071172).

21604006217608 is a wasteful number, since it uses less digits than its factorization.

21604006217608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17200642056 (or 17200642052 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 43.

The spelling of 21604006217608 in words is "twenty-one trillion, six hundred four billion, six million, two hundred seventeen thousand, six hundred eight".