81244543 has 2 divisors, whose sum is σ = 81244544. Its totient is φ = 81244542.

The previous prime is 81244531. The next prime is 81244549. The reversal of 81244543 is 34544218.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81244543 is a prime.

It is a super-3 number, since 3×81244543³ (a number of 25 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81244549) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40622271 + 40622272.

It is an arithmetic number, because the mean of its divisors is an integer number (40622272).

Almost surely, 2^81244543 is an apocalyptic number.

81244543 is a deficient number, since it is larger than the sum of its proper divisors (1).

81244543 is an equidigital number, since it uses as much as digits as its factorization.

81244543 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15360, while the sum is 31.

The square root of 81244543 is about 9013.5754836802. The cubic root of 81244543 is about 433.1098559061.

The spelling of 81244543 in words is "eighty-one million, two hundred forty-four thousand, five hundred forty-three".