43381391 has 2 divisors, whose sum is σ = 43381392. Its totient is φ = 43381390.

The previous prime is 43381379. The next prime is 43381411. The reversal of 43381391 is 19318334.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43381391 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43381301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21690695 + 21690696.

It is an arithmetic number, because the mean of its divisors is an integer number (21690696).

Almost surely, 2^43381391 is an apocalyptic number.

43381391 is a deficient number, since it is larger than the sum of its proper divisors (1).

43381391 is an equidigital number, since it uses as much as digits as its factorization.

43381391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7776, while the sum is 32.

The square root of 43381391 is about 6586.4551163733. The cubic root of 43381391 is about 351.3725451432.

The spelling of 43381391 in words is "forty-three million, three hundred eighty-one thousand, three hundred ninety-one".