3811861 has 4 divisors (see below), whose sum is σ = 3820000. Its totient is φ = 3803724.

The previous prime is 3811817. The next prime is 3811877. The reversal of 3811861 is 1681183.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1681183 = 7 ⋅240169.

It is a cyclic number.

It is not a de Polignac number, because 3811861 - 2⁷ = 3811733 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3811891) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3321 + ... + 4318.

It is an arithmetic number, because the mean of its divisors is an integer number (955000).

Almost surely, 2^3811861 is an apocalyptic number.

It is an amenable number.

3811861 is a deficient number, since it is larger than the sum of its proper divisors (8139).

3811861 is an equidigital number, since it uses as much as digits as its factorization.

3811861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8138.

The product of its digits is 1152, while the sum is 28.

The square root of 3811861 is about 1952.3987809871. The cubic root of 3811861 is about 156.2112659187.

The spelling of 3811861 in words is "three million, eight hundred eleven thousand, eight hundred sixty-one".