211721570672161 has 32 divisors (see below), whose sum is σ = 233149987721088. Its totient is φ = 190664579427840.

The previous prime is 211721570672077. The next prime is 211721570672219. The reversal of 211721570672161 is 161276075127112.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211721570672161 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (211721570672461) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 5272850461 + ... + 5272890613.

It is an arithmetic number, because the mean of its divisors is an integer number (7285937116284).

Almost surely, 2^{211721570672161} is an apocalyptic number.

It is an amenable number.

211721570672161 is a deficient number, since it is larger than the sum of its proper divisors (21428417048927).

211721570672161 is a wasteful number, since it uses less digits than its factorization.

211721570672161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49921.

The product of its (nonzero) digits is 493920, while the sum is 49.

The spelling of 211721570672161 in words is "two hundred eleven trillion, seven hundred twenty-one billion, five hundred seventy million, six hundred seventy-two thousand, one hundred sixty-one".