1728240 has 80 divisors (see below), whose sum is σ = 5654400. Its totient is φ = 435456.

The previous prime is 1728229. The next prime is 1728247. The reversal of 1728240 is 428271.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 1728240.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1728247) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4371 + ... + 4749.

It is an arithmetic number, because the mean of its divisors is an integer number (70680).

2^1728240 is an apocalyptic number.

1728240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1728240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2827200).

1728240 is an abundant number, since it is smaller than the sum of its proper divisors (3926160).

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

1728240 is a wasteful number, since it uses less digits than its factorization.

1728240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 414 (or 408 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 24.

The square root of 1728240 is about 1314.6254219358. The cubic root of 1728240 is about 120.0055552984.

1728240 divided by its sum of digits (24) gives a triangular number (72010 = T₃₇₉).

The spelling of 1728240 in words is "one million, seven hundred twenty-eight thousand, two hundred forty".