1721323 has 2 divisors, whose sum is σ = 1721324. Its totient is φ = 1721322.

The previous prime is 1721299. The next prime is 1721327. The reversal of 1721323 is 3231271.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1721323 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1721323.

It is not a weakly prime, because it can be changed into another prime (1721327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 860661 + 860662.

It is an arithmetic number, because the mean of its divisors is an integer number (860662).

2^1721323 is an apocalyptic number.

1721323 is a deficient number, since it is larger than the sum of its proper divisors (1).

1721323 is an equidigital number, since it uses as much as digits as its factorization.

1721323 is an evil number, because the sum of its binary digits is even.

The product of its digits is 252, while the sum is 19.

The square root of 1721323 is about 1311.9919969268. The cubic root of 1721323 is about 119.8452403126.

Adding to 1721323 its reverse (3231271), we get a palindrome (4952594).

The spelling of 1721323 in words is "one million, seven hundred twenty-one thousand, three hundred twenty-three".