2171321 has 4 divisors (see below), whose sum is σ = 2174352. Its totient is φ = 2168292.

The previous prime is 2171311. The next prime is 2171329. The reversal of 2171321 is 1231712.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2171321 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2171321.

It is not an unprimeable number, because it can be changed into a prime (2171329) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 230 + ... + 2096.

It is an arithmetic number, because the mean of its divisors is an integer number (543588).

2^2171321 is an apocalyptic number.

It is an amenable number.

2171321 is a deficient number, since it is larger than the sum of its proper divisors (3031).

2171321 is a wasteful number, since it uses less digits than its factorization.

2171321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3030.

The product of its digits is 84, while the sum is 17.

The square root of 2171321 is about 1473.5402946645. The cubic root of 2171321 is about 129.4915246164.

The spelling of 2171321 in words is "two million, one hundred seventy-one thousand, three hundred twenty-one".