1722109 has 4 divisors (see below), whose sum is σ = 1728604. Its totient is φ = 1715616.

The previous prime is 1722089. The next prime is 1722113. The reversal of 1722109 is 9012271.

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 765625 + 956484 = 875^2 + 978^2 .

It is a cyclic number.

It is not a de Polignac number, because 1722109 - 2¹⁹ = 1197821 is a prime.

It is a Duffinian number.

1722109 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 1722109.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1722199) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2832 + ... + 3385.

It is an arithmetic number, because the mean of its divisors is an integer number (432151).

2^1722109 is an apocalyptic number.

It is an amenable number.

1722109 is a deficient number, since it is larger than the sum of its proper divisors (6495).

1722109 is an equidigital number, since it uses as much as digits as its factorization.

1722109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6494.

The product of its (nonzero) digits is 252, while the sum is 22.

The square root of 1722109 is about 1312.2915072498. The cubic root of 1722109 is about 119.8634790016.

The spelling of 1722109 in words is "one million, seven hundred twenty-two thousand, one hundred nine".