1660005 has 24 divisors (see below), whose sum is σ = 2958072. Its totient is φ = 860544.

The previous prime is 1659997. The next prime is 1660007. The reversal of 1660005 is 5000661.

1660005 is a `hidden beast` number, since 1 + 660 + 0 + 0 + 5 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 772641 + 887364 = 879^2 + 942^2 .

It is not a de Polignac number, because 1660005 - 2³ = 1659997 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1660005.

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 23 ways as a sum of consecutive naturals, for example, 1167 + ... + 2163.

It is an arithmetic number, because the mean of its divisors is an integer number (123253).

2^1660005 is an apocalyptic number.

1660005 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1660005 is a deficient number, since it is larger than the sum of its proper divisors (1298067).

1660005 is a wasteful number, since it uses less digits than its factorization.

1660005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1045 (or 1042 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 18.

The square root of 1660005 is about 1288.4118130474. The cubic root of 1660005 is about 118.4049336345.

Adding to 1660005 its reverse (5000661), we get a palindrome (6660666).

The spelling of 1660005 in words is "one million, six hundred sixty thousand, five".