43520381 has 2 divisors, whose sum is σ = 43520382. Its totient is φ = 43520380.

The previous prime is 43520371. The next prime is 43520383. The reversal of 43520381 is 18302534.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 26988025 + 16532356 = 5195^2 + 4066^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43520381 is a prime.

It is a super-2 number, since 2×43520381² = 3788047124770322, which contains 22 as substring.

Together with 43520383, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 43520381.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43520383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21760190 + 21760191.

It is an arithmetic number, because the mean of its divisors is an integer number (21760191).

Almost surely, 2^43520381 is an apocalyptic number.

It is an amenable number.

43520381 is a deficient number, since it is larger than the sum of its proper divisors (1).

43520381 is an equidigital number, since it uses as much as digits as its factorization.

43520381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 43520381 is about 6596.9978778229. The cubic root of 43520381 is about 351.7474002354.

The spelling of 43520381 in words is "forty-three million, five hundred twenty thousand, three hundred eighty-one".