3813538581 has 12 divisors (see below), whose sum is σ = 5586029280. Its totient is φ = 2506550760.

The previous prime is 3813538567. The next prime is 3813538609. The reversal of 3813538581 is 1858353183.

3813538581 is a `hidden beast` number, since 3 + 8 + 1 + 35 + 38 + 581 = 666.

It is not a de Polignac number, because 3813538581 - 2⁶ = 3813538517 is a prime.

It is a super-2 number, since 2×3813538581² = 29086153017550987122, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3813538181) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 2983351 + ... + 2984628.

It is an arithmetic number, because the mean of its divisors is an integer number (465502440).

Almost surely, 2^3813538581 is an apocalyptic number.

It is an amenable number.

3813538581 is a deficient number, since it is larger than the sum of its proper divisors (1772490699).

3813538581 is a wasteful number, since it uses less digits than its factorization.

3813538581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5968056 (or 5968053 counting only the distinct ones).

The product of its digits is 345600, while the sum is 45.

The square root of 3813538581 is about 61753.8547865637. The cubic root of 3813538581 is about 1562.3417849059.

The spelling of 3813538581 in words is "three billion, eight hundred thirteen million, five hundred thirty-eight thousand, five hundred eighty-one".