2216656506221 has 16 divisors (see below), whose sum is σ = 2325736586160. Its totient is φ = 2109934579200.

The previous prime is 2216656506209. The next prime is 2216656506257. The reversal of 2216656506221 is 1226056566122.

It can be written as a sum of positive squares in 8 ways, for example, as 44316565225 + 2172339940996 = 210515^2 + 1473886^2 .

It is a de Polignac number, because none of the positive numbers 2^k-2216656506221 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 (2216656506121) 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, 941570 + ... + 2306483.

It is an arithmetic number, because the mean of its divisors is an integer number (145358536635).

Almost surely, 2^{2216656506221} is an apocalyptic number.

It is an amenable number.

2216656506221 is a deficient number, since it is larger than the sum of its proper divisors (109080079939).

2216656506221 is a wasteful number, since it uses less digits than its factorization.

2216656506221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3248416.

The product of its (nonzero) digits is 518400, while the sum is 44.

The spelling of 2216656506221 in words is "two trillion, two hundred sixteen billion, six hundred fifty-six million, five hundred six thousand, two hundred twenty-one".