81383543 has 2 divisors, whose sum is σ = 81383544. Its totient is φ = 81383542.

The previous prime is 81383521. The next prime is 81383569. The reversal of 81383543 is 34538318.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81383543 - 2¹² = 81379447 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81383513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40691771 + 40691772.

It is an arithmetic number, because the mean of its divisors is an integer number (40691772).

Almost surely, 2^81383543 is an apocalyptic number.

81383543 is a deficient number, since it is larger than the sum of its proper divisors (1).

81383543 is an equidigital number, since it uses as much as digits as its factorization.

81383543 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34560, while the sum is 35.

The square root of 81383543 is about 9021.2827801815. The cubic root of 81383543 is about 433.3567154378.

The spelling of 81383543 in words is "eighty-one million, three hundred eighty-three thousand, five hundred forty-three".