1720745 has 16 divisors (see below), whose sum is σ = 2322432. Its totient is φ = 1214400.

The previous prime is 1720711. The next prime is 1720769. The reversal of 1720745 is 5470271.

It is not a de Polignac number, because 1720745 - 2¹⁰ = 1719721 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 920 + ... + 2070.

It is an arithmetic number, because the mean of its divisors is an integer number (145152).

2^1720745 is an apocalyptic number.

It is an amenable number.

1720745 is a deficient number, since it is larger than the sum of its proper divisors (601687).

1720745 is a wasteful number, since it uses less digits than its factorization.

1720745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1192.

The product of its (nonzero) digits is 1960, while the sum is 26.

The square root of 1720745 is about 1311.7717026983. The cubic root of 1720745 is about 119.8318246039.

The spelling of 1720745 in words is "one million, seven hundred twenty thousand, seven hundred forty-five".