2171564123217 has 8 divisors (see below), whose sum is σ = 2895428680224. Its totient is φ = 1447704490848.

The previous prime is 2171564123171. The next prime is 2171564123227. The reversal of 2171564123217 is 7123214651712.

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

It is not a de Polignac number, because 2171564123217 - 2²³ = 2171555734609 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2171564123227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36703 + ... + 2084340.

It is an arithmetic number, because the mean of its divisors is an integer number (361928585028).

Almost surely, 2^{2171564123217} is an apocalyptic number.

It is an amenable number.

2171564123217 is a deficient number, since it is larger than the sum of its proper divisors (723864557007).

2171564123217 is a wasteful number, since it uses less digits than its factorization.

2171564123217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2462319.

The product of its digits is 141120, while the sum is 42.

Adding to 2171564123217 its reverse (7123214651712), we get a palindrome (9294778774929).

The spelling of 2171564123217 in words is "two trillion, one hundred seventy-one billion, five hundred sixty-four million, one hundred twenty-three thousand, two hundred seventeen".