2001660 has 48 divisors (see below), whose sum is σ = 5693856. Its totient is φ = 525312.

The previous prime is 2001653. The next prime is 2001673. The reversal of 2001660 is 661002.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4152 + ... + 4608.

It is an arithmetic number, because the mean of its divisors is an integer number (118622).

2^2001660 is an apocalyptic number.

2001660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2001660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2846928).

2001660 is an abundant number, since it is smaller than the sum of its proper divisors (3692196).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2001660 is a wasteful number, since it uses less digits than its factorization.

2001660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 542 (or 540 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 2001660 is about 1414.8003392705. The cubic root of 2001660 is about 126.0269531656.

Adding to 2001660 its reverse (661002), we get a palindrome (2662662).

The spelling of 2001660 in words is "two million, one thousand, six hundred sixty".