4000003999991 has 16 divisors (see below), whose sum is σ = 4143601271040. Its totient is φ = 3858734194560.

The previous prime is 4000003999951. The next prime is 4000004000017. The reversal of 4000003999991 is 1999993000004.

It is a cyclic number.

It is not a de Polignac number, because 4000003999991 - 2²⁶ = 3999936891127 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4000003999951) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11676671 + ... + 12014351.

It is an arithmetic number, because the mean of its divisors is an integer number (258975079440).

Almost surely, 2^{4000003999991} is an apocalyptic number.

4000003999991 is a deficient number, since it is larger than the sum of its proper divisors (143597271049).

4000003999991 is a wasteful number, since it uses less digits than its factorization.

4000003999991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 341126.

The product of its (nonzero) digits is 708588, while the sum is 53.

Adding to 4000003999991 its reverse (1999993000004), we get a palindrome (5999996999995).

It can be divided in two parts, 4000003 and 999991, that added together give a palindrome (4999994).

The spelling of 4000003999991 in words is "four trillion, three million, nine hundred ninety-nine thousand, nine hundred ninety-one".