81343733 has 2 divisors, whose sum is σ = 81343734. Its totient is φ = 81343732.

The previous prime is 81343697. The next prime is 81343747. The reversal of 81343733 is 33734318.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63888049 + 17455684 = 7993^2 + 4178^2 .

It is a cyclic number.

It is not a de Polignac number, because 81343733 - 2¹⁴ = 81327349 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81343733.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81343763) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40671866 + 40671867.

It is an arithmetic number, because the mean of its divisors is an integer number (40671867).

Almost surely, 2^81343733 is an apocalyptic number.

It is an amenable number.

81343733 is a deficient number, since it is larger than the sum of its proper divisors (1).

81343733 is an equidigital number, since it uses as much as digits as its factorization.

81343733 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18144, while the sum is 32.

The square root of 81343733 is about 9019.0760613269. The cubic root of 81343733 is about 433.2860428998.

The spelling of 81343733 in words is "eighty-one million, three hundred forty-three thousand, seven hundred thirty-three".