3815891 has 2 divisors, whose sum is σ = 3815892. Its totient is φ = 3815890.

The previous prime is 3815879. The next prime is 3815893. The reversal of 3815891 is 1985183.

It is a strong prime.

It is an emirp because it is prime and its reverse (1985183) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3815891 is a prime.

It is a super-2 number, since 2×3815891² = 29122048247762, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 3815893, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (3815893) 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 as a sum of consecutive naturals, namely, 1907945 + 1907946.

It is an arithmetic number, because the mean of its divisors is an integer number (1907946).

Almost surely, 2^3815891 is an apocalyptic number.

3815891 is a deficient number, since it is larger than the sum of its proper divisors (1).

3815891 is an equidigital number, since it uses as much as digits as its factorization.

3815891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8640, while the sum is 35.

The square root of 3815891 is about 1953.4305720962. The cubic root of 3815891 is about 156.2662967535.

The spelling of 3815891 in words is "three million, eight hundred fifteen thousand, eight hundred ninety-one".