1687109 has 4 divisors (see below), whose sum is σ = 1728300. Its totient is φ = 1645920.

The previous prime is 1687087. The next prime is 1687111. The reversal of 1687109 is 9017861.

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

It can be written as a sum of positive squares in 2 ways, for example, as 124609 + 1562500 = 353^2 + 1250^2 .

It is a cyclic number.

It is not a de Polignac number, because 1687109 - 2¹² = 1683013 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 (1687129) 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, 20534 + ... + 20615.

It is an arithmetic number, because the mean of its divisors is an integer number (432075).

2^1687109 is an apocalyptic number.

It is an amenable number.

1687109 is a deficient number, since it is larger than the sum of its proper divisors (41191).

1687109 is an equidigital number, since it uses as much as digits as its factorization.

1687109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41190.

The product of its (nonzero) digits is 3024, while the sum is 32.

The square root of 1687109 is about 1298.8876009879. The cubic root of 1687109 is about 119.0458830198.

The spelling of 1687109 in words is "one million, six hundred eighty-seven thousand, one hundred nine".