211656560721005 has 16 divisors (see below), whose sum is σ = 268931246330304. Its totient is φ = 159363215182080.

The previous prime is 211656560720993. The next prime is 211656560721019. The reversal of 211656560721005 is 500127065656112.

It is a de Polignac number, because none of the positive numbers 2^k-211656560721005 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5546051 + ... + 21308960.

It is an arithmetic number, because the mean of its divisors is an integer number (16808202895644).

Almost surely, 2^{211656560721005} is an apocalyptic number.

It is an amenable number.

211656560721005 is a deficient number, since it is larger than the sum of its proper divisors (57274685609299).

211656560721005 is a wasteful number, since it uses less digits than its factorization.

211656560721005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26947756.

The product of its (nonzero) digits is 756000, while the sum is 47.

The spelling of 211656560721005 in words is "two hundred eleven trillion, six hundred fifty-six billion, five hundred sixty million, seven hundred twenty-one thousand, five".