43156381 has 2 divisors, whose sum is σ = 43156382. Its totient is φ = 43156380.

The previous prime is 43156339. The next prime is 43156397. The reversal of 43156381 is 18365134.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42968025 + 188356 = 6555^2 + 434^2 .

It is a cyclic number.

It is not a de Polignac number, because 43156381 - 2⁹ = 43155869 is a prime.

It is a super-2 number, since 2×43156381² = 3724946442034322, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43156301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21578190 + 21578191.

It is an arithmetic number, because the mean of its divisors is an integer number (21578191).

Almost surely, 2^43156381 is an apocalyptic number.

It is an amenable number.

43156381 is a deficient number, since it is larger than the sum of its proper divisors (1).

43156381 is an equidigital number, since it uses as much as digits as its factorization.

43156381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8640, while the sum is 31.

The square root of 43156381 is about 6569.3516422856. The cubic root of 43156381 is about 350.7639936963.

The spelling of 43156381 in words is "forty-three million, one hundred fifty-six thousand, three hundred eighty-one".