2001320636 has 48 divisors (see below), whose sum is σ = 4043483136. Its totient is φ = 849006144.

The previous prime is 2001320627. The next prime is 2001320681. The reversal of 2001320636 is 6360231002.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1229255 + ... + 1230881.

It is an arithmetic number, because the mean of its divisors is an integer number (84239232).

Almost surely, 2^2001320636 is an apocalyptic number.

It is an amenable number.

2001320636 is an abundant number, since it is smaller than the sum of its proper divisors (2042162500).

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

2001320636 is a wasteful number, since it uses less digits than its factorization.

2001320636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2058 (or 2056 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 23.

The square root of 2001320636 is about 44736.1222727227. The cubic root of 2001320636 is about 1260.1983050609.

Adding to 2001320636 its reverse (6360231002), we get a palindrome (8361551638).

The spelling of 2001320636 in words is "two billion, one million, three hundred twenty thousand, six hundred thirty-six".