1722289 has 4 divisors (see below), whose sum is σ = 1745956. Its totient is φ = 1698624.

The previous prime is 1722283. The next prime is 1722307. The reversal of 1722289 is 9822271.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 501264 + 1221025 = 708^2 + 1105^2 .

It is a cyclic number.

It is not a de Polignac number, because 1722289 - 2¹⁵ = 1689521 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 1722289.

It is not an unprimeable number, because it can be changed into a prime (1722283) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11724 + ... + 11869.

It is an arithmetic number, because the mean of its divisors is an integer number (436489).

2^1722289 is an apocalyptic number.

It is an amenable number.

1722289 is a deficient number, since it is larger than the sum of its proper divisors (23667).

1722289 is an equidigital number, since it uses as much as digits as its factorization.

1722289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23666.

The product of its digits is 4032, while the sum is 31.

The square root of 1722289 is about 1312.3600877808. The cubic root of 1722289 is about 119.8676550196.

The spelling of 1722289 in words is "one million, seven hundred twenty-two thousand, two hundred eighty-nine".