1720240 has 20 divisors (see below), whose sum is σ = 3999744. Its totient is φ = 688064.

The previous prime is 1720231. The next prime is 1720273. The reversal of 1720240 is 420271.

It is a tau number, because it is divible by the number of its divisors (20).

It is a Harshad number since it is a multiple of its sum of digits (16).

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, 10672 + ... + 10831.

2^1720240 is an apocalyptic number.

1720240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1720240 is an abundant number, since it is smaller than the sum of its proper divisors (2279504).

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

1720240 is a wasteful number, since it uses less digits than its factorization.

1720240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21516 (or 21510 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 16.

The square root of 1720240 is about 1311.5792008110. The cubic root of 1720240 is about 119.8201008075.

The spelling of 1720240 in words is "one million, seven hundred twenty thousand, two hundred forty".