1660001 has 4 divisors (see below), whose sum is σ = 1897152. Its totient is φ = 1422852.

The previous prime is 1659997. The next prime is 1660007. The reversal of 1660001 is 1000661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1660001 - 2² = 1659997 is a prime.

It is an Ulam number.

It is a Duffinian 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 3 ways as a sum of consecutive naturals, for example, 118565 + ... + 118578.

It is an arithmetic number, because the mean of its divisors is an integer number (474288).

2^1660001 is an apocalyptic number.

It is an amenable number.

1660001 is a deficient number, since it is larger than the sum of its proper divisors (237151).

1660001 is an equidigital number, since it uses as much as digits as its factorization.

1660001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 237150.

The product of its (nonzero) digits is 36, while the sum is 14.

The square root of 1660001 is about 1288.4102607477. The cubic root of 1660001 is about 118.4048385304.

Adding to 1660001 its reverse (1000661), we get a palindrome (2660662).

The spelling of 1660001 in words is "one million, six hundred sixty thousand, one".