43542581 has 2 divisors, whose sum is σ = 43542582. Its totient is φ = 43542580.

The previous prime is 43542523. The next prime is 43542589. The reversal of 43542581 is 18524534.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 41396356 + 2146225 = 6434^2 + 1465^2 .

It is a cyclic number.

It is not a de Polignac number, because 43542581 - 2⁶ = 43542517 is a prime.

It is a super-2 number, since 2×43542581² = 3791912720283122, 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 (43542589) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21771290 + 21771291.

It is an arithmetic number, because the mean of its divisors is an integer number (21771291).

Almost surely, 2^43542581 is an apocalyptic number.

It is an amenable number.

43542581 is a deficient number, since it is larger than the sum of its proper divisors (1).

43542581 is an equidigital number, since it uses as much as digits as its factorization.

43542581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 19200, while the sum is 32.

The square root of 43542581 is about 6598.6802468372. The cubic root of 43542581 is about 351.8071995349.

The spelling of 43542581 in words is "forty-three million, five hundred forty-two thousand, five hundred eighty-one".