2171621211717 has 8 divisors (see below), whose sum is σ = 2895548887296. Its totient is φ = 1447720505312.

The previous prime is 2171621211703. The next prime is 2171621211737. The reversal of 2171621211717 is 7171121261712.

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 2171621211717 - 2¹⁴ = 2171621195333 is a prime.

It is a super-2 number, since 2×2171621211717² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2171621211737) 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, 6553653 + ... + 6877034.

It is an arithmetic number, because the mean of its divisors is an integer number (361943610912).

Almost surely, 2^{2171621211717} is an apocalyptic number.

It is an amenable number.

2171621211717 is a deficient number, since it is larger than the sum of its proper divisors (723927675579).

2171621211717 is a wasteful number, since it uses less digits than its factorization.

2171621211717 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13484587.

The product of its digits is 16464, while the sum is 39.

The spelling of 2171621211717 in words is "two trillion, one hundred seventy-one billion, six hundred twenty-one million, two hundred eleven thousand, seven hundred seventeen".