81504743 has 2 divisors, whose sum is σ = 81504744. Its totient is φ = 81504742.

The previous prime is 81504739. The next prime is 81504767. The reversal of 81504743 is 34740518.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81504743 - 2² = 81504739 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81504713) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40752371 + 40752372.

It is an arithmetic number, because the mean of its divisors is an integer number (40752372).

Almost surely, 2^81504743 is an apocalyptic number.

81504743 is a deficient number, since it is larger than the sum of its proper divisors (1).

81504743 is an equidigital number, since it uses as much as digits as its factorization.

81504743 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13440, while the sum is 32.

The square root of 81504743 is about 9027.9977292864. The cubic root of 81504743 is about 433.5717334477.

The spelling of 81504743 in words is "eighty-one million, five hundred four thousand, seven hundred forty-three".