2001440839 has 4 divisors (see below), whose sum is σ = 2002786480. Its totient is φ = 2000095200.

The previous prime is 2001440801. The next prime is 2001440843. The reversal of 2001440839 is 9380441002.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9380441002 = 2 ⋅4690220501.

It is a cyclic number.

It is not a de Polignac number, because 2001440839 - 2⁹ = 2001440327 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2001440839.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001441839) 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, 670587 + ... + 673564.

It is an arithmetic number, because the mean of its divisors is an integer number (500696620).

Almost surely, 2^2001440839 is an apocalyptic number.

2001440839 is a deficient number, since it is larger than the sum of its proper divisors (1345641).

2001440839 is a wasteful number, since it uses less digits than its factorization.

2001440839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1345640.

The product of its (nonzero) digits is 6912, while the sum is 31.

The square root of 2001440839 is about 44737.4657194616. The cubic root of 2001440839 is about 1260.2235344988.

The spelling of 2001440839 in words is "two billion, one million, four hundred forty thousand, eight hundred thirty-nine".