1728406 has 4 divisors (see below), whose sum is σ = 2592612. Its totient is φ = 864202.

The previous prime is 1728403. The next prime is 1728409. The reversal of 1728406 is 6048271.

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

It is an interprime number because it is at equal distance from previous prime (1728403) and next prime (1728409).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1728403) 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 as a sum of consecutive naturals, namely, 432100 + ... + 432103.

It is an arithmetic number, because the mean of its divisors is an integer number (648153).

2^1728406 is an apocalyptic number.

1728406 is a deficient number, since it is larger than the sum of its proper divisors (864206).

1728406 is an equidigital number, since it uses as much as digits as its factorization.

1728406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 864205.

The product of its (nonzero) digits is 2688, while the sum is 28.

The square root of 1728406 is about 1314.6885562748. The cubic root of 1728406 is about 120.0093974122.

The spelling of 1728406 in words is "one million, seven hundred twenty-eight thousand, four hundred six".