1720256 has 14 divisors (see below), whose sum is σ = 3413760. Its totient is φ = 860096.

The previous prime is 1720231. The next prime is 1720273. The reversal of 1720256 is 6520271.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 13376 + ... + 13503.

It is an arithmetic number, because the mean of its divisors is an integer number (243840).

2^1720256 is an apocalyptic number.

1720256 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1720256 is a deficient number, since it is larger than the sum of its proper divisors (1693504).

1720256 is an equidigital number, since it uses as much as digits as its factorization.

1720256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26891 (or 26881 counting only the distinct ones).

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

The square root of 1720256 is about 1311.5853003141. The cubic root of 1720256 is about 119.8204722897.

The spelling of 1720256 in words is "one million, seven hundred twenty thousand, two hundred fifty-six".