80689729 has 2 divisors, whose sum is σ = 80689730. Its totient is φ = 80689728.

The previous prime is 80689717. The next prime is 80689759. The reversal of 80689729 is 92798608.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 42928704 + 37761025 = 6552^2 + 6145^2 .

It is a cyclic number.

It is not a de Polignac number, because 80689729 - 2¹³ = 80681537 is a prime.

It is not a weakly prime, because it can be changed into another prime (80689759) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40344864 + 40344865.

It is an arithmetic number, because the mean of its divisors is an integer number (40344865).

Almost surely, 2^80689729 is an apocalyptic number.

It is an amenable number.

80689729 is a deficient number, since it is larger than the sum of its proper divisors (1).

80689729 is an equidigital number, since it uses as much as digits as its factorization.

80689729 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 435456, while the sum is 49.

The square root of 80689729 is about 8982.7461836568. The cubic root of 80689729 is about 432.1217096055.

It can be divided in two parts, 80689 and 729, that added together give a palindrome (81418).

The spelling of 80689729 in words is "eighty million, six hundred eighty-nine thousand, seven hundred twenty-nine".