2164321 has 6 divisors (see below), whose sum is σ = 2299430. Its totient is φ = 2036736.

The previous prime is 2164313. The next prime is 2164367. The reversal of 2164321 is 1234612.

It can be written as a sum of positive squares in 3 ways, for example, as 876096 + 1288225 = 936^2 + 1135^2 .

It is not a de Polignac number, because 2164321 - 2³ = 2164313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2164121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3456 + ... + 4033.

2^2164321 is an apocalyptic number.

It is an amenable number.

2164321 is a deficient number, since it is larger than the sum of its proper divisors (135109).

2164321 is an equidigital number, since it uses as much as digits as its factorization.

2164321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7523 (or 7506 counting only the distinct ones).

The product of its digits is 288, while the sum is 19.

The square root of 2164321 is about 1471.1631452698. The cubic root of 2164321 is about 129.3522213236.

Adding to 2164321 its reverse (1234612), we get a palindrome (3398933).

It can be divided in two parts, 2164 and 321, that added together give a triangular number (2485 = T₇₀).

The spelling of 2164321 in words is "two million, one hundred sixty-four thousand, three hundred twenty-one".