3811945 has 4 divisors (see below), whose sum is σ = 4574340. Its totient is φ = 3049552.

The previous prime is 3811939. The next prime is 3811949. The reversal of 3811945 is 5491183.

3811945 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5491183 = 179 ⋅30677.

It can be written as a sum of positive squares in 2 ways, for example, as 514089 + 3297856 = 717^2 + 1816^2 .

It is a cyclic number.

It is not a de Polignac number, because 3811945 - 2⁷ = 3811817 is a prime.

It is not an unprimeable number, because it can be changed into a prime (3811949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 381190 + ... + 381199.

It is an arithmetic number, because the mean of its divisors is an integer number (1143585).

Almost surely, 2^3811945 is an apocalyptic number.

It is an amenable number.

3811945 is a deficient number, since it is larger than the sum of its proper divisors (762395).

3811945 is an equidigital number, since it uses as much as digits as its factorization.

3811945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 762394.

The product of its digits is 4320, while the sum is 31.

The square root of 3811945 is about 1952.4202928673. The cubic root of 3811945 is about 156.2124133591.

The spelling of 3811945 in words is "three million, eight hundred eleven thousand, nine hundred forty-five".