81496729 has 2 divisors, whose sum is σ = 81496730. Its totient is φ = 81496728.

The previous prime is 81496717. The next prime is 81496741. The reversal of 81496729 is 92769418.

It is a balanced prime because it is at equal distance from previous prime (81496717) and next prime (81496741).

It can be written as a sum of positive squares in only one way, i.e., 81486729 + 10000 = 9027^2 + 100^2 .

It is a cyclic number.

It is not a de Polignac number, because 81496729 - 2⁵ = 81496697 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is not a weakly prime, because it can be changed into another prime (81496769) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40748364 + 40748365.

It is an arithmetic number, because the mean of its divisors is an integer number (40748365).

Almost surely, 2^81496729 is an apocalyptic number.

It is an amenable number.

81496729 is a deficient number, since it is larger than the sum of its proper divisors (1).

81496729 is an equidigital number, since it uses as much as digits as its factorization.

81496729 is an evil number, because the sum of its binary digits is even.

The product of its digits is 217728, while the sum is 46.

The square root of 81496729 is about 9027.5538768816. The cubic root of 81496729 is about 433.5575225865.

It can be divided in two parts, 8149 and 6729, that added together give a triangular number (14878 = T₁₇₂).

The spelling of 81496729 in words is "eighty-one million, four hundred ninety-six thousand, seven hundred twenty-nine".