3811965 has 16 divisors (see below), whose sum is σ = 6191808. Its totient is φ = 2002176.

The previous prime is 3811949. The next prime is 3811967. The reversal of 3811965 is 5691183.

It is not a de Polignac number, because 3811965 - 2⁴ = 3811949 is a prime.

It is a super-2 number, since 2×3811965² = 29062154322450, which contains 22 as substring.

3811965 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3811967) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 892 + ... + 2901.

It is an arithmetic number, because the mean of its divisors is an integer number (386988).

Almost surely, 2^3811965 is an apocalyptic number.

It is an amenable number.

3811965 is a deficient number, since it is larger than the sum of its proper divisors (2379843).

3811965 is a wasteful number, since it uses less digits than its factorization.

3811965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3868.

The product of its digits is 6480, while the sum is 33.

The square root of 3811965 is about 1952.4254147086. The cubic root of 3811965 is about 156.2126865567.

It can be divided in two parts, 381 and 1965, that added together give a triangular number (2346 = T₆₈).

The spelling of 3811965 in words is "three million, eight hundred eleven thousand, nine hundred sixty-five".