1660009 has 8 divisors (see below), whose sum is σ = 1801800. Its totient is φ = 1520256.

The previous prime is 1660007. The next prime is 1660037. The reversal of 1660009 is 9000661.

It can be written as a sum of positive squares in 4 ways, for example, as 90000 + 1570009 = 300^2 + 1253^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1660009 - 2¹ = 1660007 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1660007) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1509 + ... + 2365.

It is an arithmetic number, because the mean of its divisors is an integer number (225225).

2^1660009 is an apocalyptic number.

It is an amenable number.

1660009 is a deficient number, since it is larger than the sum of its proper divisors (141791).

1660009 is a wasteful number, since it uses less digits than its factorization.

1660009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1019.

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 1660009 is about 1288.4133653451. The cubic root of 1660009 is about 118.4050287385.

It can be divided in two parts, 16 and 60009, that added together give a square (60025 = 245²).

The spelling of 1660009 in words is "one million, six hundred sixty thousand, nine".