2001720 has 64 divisors (see below), whose sum is σ = 6865920. Its totient is φ = 457344.

The previous prime is 2001709. The next prime is 2001721. The reversal of 2001720 is 271002.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a zygodrome in base 13.

It is a junction number, because it is equal to n+sod(n) for n = 2001696 and 2001705.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 352 + ... + 2031.

It is an arithmetic number, because the mean of its divisors is an integer number (107280).

2^2001720 is an apocalyptic number.

2001720 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 2001720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3432960).

2001720 is an abundant number, since it is smaller than the sum of its proper divisors (4864200).

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

2001720 is a wasteful number, since it uses less digits than its factorization.

2001720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2404 (or 2400 counting only the distinct ones).

The product of its (nonzero) digits is 28, while the sum is 12.

The square root of 2001720 is about 1414.8215435171. The cubic root of 2001720 is about 126.0282123774.

Adding to 2001720 its reverse (271002), we get a palindrome (2272722).

The spelling of 2001720 in words is "two million, one thousand, seven hundred twenty".