16506560221 has 8 divisors (see below), whose sum is σ = 16611980000. Its totient is φ = 16401430800.

The previous prime is 16506560209. The next prime is 16506560233. The reversal of 16506560221 is 12206560561.

It is an interprime number because it is at equal distance from previous prime (16506560209) and next prime (16506560233).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 16506560221 - 2⁷ = 16506560093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16506560201) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42046 + ... + 186496.

It is an arithmetic number, because the mean of its divisors is an integer number (2076497500).

Almost surely, 2^16506560221 is an apocalyptic number.

It is an amenable number.

16506560221 is a deficient number, since it is larger than the sum of its proper divisors (105419779).

16506560221 is a wasteful number, since it uses less digits than its factorization.

16506560221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145179.

The product of its (nonzero) digits is 21600, while the sum is 34.

The spelling of 16506560221 in words is "sixteen billion, five hundred six million, five hundred sixty thousand, two hundred twenty-one".