1720265 has 4 divisors (see below), whose sum is σ = 2064324. Its totient is φ = 1376208.

The previous prime is 1720231. The next prime is 1720273. The reversal of 1720265 is 5620271.

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 1190281 + 529984 = 1091^2 + 728^2 .

It is a cyclic number.

It is not a de Polignac number, because 1720265 - 2¹⁰ = 1719241 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 1720265.

It is an unprimeable number.

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, 172022 + ... + 172031.

It is an arithmetic number, because the mean of its divisors is an integer number (516081).

2^1720265 is an apocalyptic number.

It is an amenable number.

1720265 is a deficient number, since it is larger than the sum of its proper divisors (344059).

1720265 is an equidigital number, since it uses as much as digits as its factorization.

1720265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 344058.

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 1720265 is about 1311.5887312721. The cubic root of 1720265 is about 119.8206812474.

The spelling of 1720265 in words is "one million, seven hundred twenty thousand, two hundred sixty-five".