80718809 has 2 divisors, whose sum is σ = 80718810. Its totient is φ = 80718808.

The previous prime is 80718779. The next prime is 80718811. The reversal of 80718809 is 90881708.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 52128400 + 28590409 = 7220^2 + 5347^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-80718809 is a prime.

It is a super-2 number, since 2×80718809² = 13031052252756962, which contains 22 as substring.

Together with 80718811, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (80717809) 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, 40359404 + 40359405.

It is an arithmetic number, because the mean of its divisors is an integer number (40359405).

Almost surely, 2^80718809 is an apocalyptic number.

It is an amenable number.

80718809 is a deficient number, since it is larger than the sum of its proper divisors (1).

80718809 is an equidigital number, since it uses as much as digits as its factorization.

80718809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32256, while the sum is 41.

The square root of 80718809 is about 8984.3646965158. The cubic root of 80718809 is about 432.1736145596.

The spelling of 80718809 in words is "eighty million, seven hundred eighteen thousand, eight hundred nine".