1728664 has 16 divisors (see below), whose sum is σ = 3704400. Its totient is φ = 740832.

The previous prime is 1728659. The next prime is 1728689. The reversal of 1728664 is 4668271.

It is an Ulam number.

It is a d-powerful number, because it can be written as 1 + 7³ + 2⁹ + 8³ + 6⁶ + 6⁸ + 4⁵ .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15379 + ... + 15490.

It is an arithmetic number, because the mean of its divisors is an integer number (231525).

2^1728664 is an apocalyptic number.

1728664 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

1728664 is an abundant number, since it is smaller than the sum of its proper divisors (1975736).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1728664 is a wasteful number, since it uses less digits than its factorization.

1728664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30882 (or 30878 counting only the distinct ones).

The product of its digits is 16128, while the sum is 34.

The square root of 1728664 is about 1314.7866747119. The cubic root of 1728664 is about 120.0153684021.

It can be divided in two parts, 172 and 8664, that added together give a square (8836 = 94²).

The spelling of 1728664 in words is "one million, seven hundred twenty-eight thousand, six hundred sixty-four".