43955381 has 2 divisors, whose sum is σ = 43955382. Its totient is φ = 43955380.

The previous prime is 43955377. The next prime is 43955383. The reversal of 43955381 is 18355934.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 41809156 + 2146225 = 6466^2 + 1465^2 .

It is a cyclic number.

It is not a de Polignac number, because 43955381 - 2² = 43955377 is a prime.

It is a super-2 number, since 2×43955381² = 3864151037710322, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 43955383, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43955383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21977690 + 21977691.

It is an arithmetic number, because the mean of its divisors is an integer number (21977691).

Almost surely, 2^43955381 is an apocalyptic number.

It is an amenable number.

43955381 is a deficient number, since it is larger than the sum of its proper divisors (1).

43955381 is an equidigital number, since it uses as much as digits as its factorization.

43955381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 64800, while the sum is 38.

The square root of 43955381 is about 6629.8854439575. The cubic root of 43955381 is about 352.9154593751.

The spelling of 43955381 in words is "forty-three million, nine hundred fifty-five thousand, three hundred eighty-one".