4001311665 has 24 divisors (see below), whose sum is σ = 7469116200. Its totient is φ = 1969876224.

The previous prime is 4001311591. The next prime is 4001311711. The reversal of 4001311665 is 5661131004.

It can be written as a sum of positive squares in 4 ways, for example, as 696326544 + 3304985121 = 26388^2 + 57489^2 .

It is not a de Polignac number, because 4001311665 - 2⁷ = 4001311537 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3419340 + ... + 3420509.

It is an arithmetic number, because the mean of its divisors is an integer number (311213175).

Almost surely, 2^4001311665 is an apocalyptic number.

4001311665 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

It is an amenable number.

4001311665 is a deficient number, since it is larger than the sum of its proper divisors (3467804535).

4001311665 is a wasteful number, since it uses less digits than its factorization.

4001311665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6839873 (or 6839870 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 4001311665 is about 63255.9219757328. The cubic root of 4001311665 is about 1587.5745445393.

Adding to 4001311665 its reverse (5661131004), we get a palindrome (9662442669).

The spelling of 4001311665 in words is "four billion, one million, three hundred eleven thousand, six hundred sixty-five".