1720487 has 4 divisors (see below), whose sum is σ = 1723176. Its totient is φ = 1717800.

The previous prime is 1720471. The next prime is 1720513. The reversal of 1720487 is 7840271.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1720487 - 2⁴ = 1720471 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1720427) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 233 + ... + 1869.

It is an arithmetic number, because the mean of its divisors is an integer number (430794).

2^1720487 is an apocalyptic number.

1720487 is a deficient number, since it is larger than the sum of its proper divisors (2689).

1720487 is a wasteful number, since it uses less digits than its factorization.

1720487 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2688.

The product of its (nonzero) digits is 3136, while the sum is 29.

The square root of 1720487 is about 1311.6733587292. The cubic root of 1720487 is about 119.8258353074.

The spelling of 1720487 in words is "one million, seven hundred twenty thousand, four hundred eighty-seven".