80505779 has 2 divisors, whose sum is σ = 80505780. Its totient is φ = 80505778.

The previous prime is 80505757. The next prime is 80505797. The reversal of 80505779 is 97750508.

It is a happy number.

Together with next prime (80505797) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 80505779 - 2¹² = 80501683 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (80505749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40252889 + 40252890.

It is an arithmetic number, because the mean of its divisors is an integer number (40252890).

Almost surely, 2^80505779 is an apocalyptic number.

80505779 is a deficient number, since it is larger than the sum of its proper divisors (1).

80505779 is an equidigital number, since it uses as much as digits as its factorization.

80505779 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 88200, while the sum is 41.

The square root of 80505779 is about 8972.5012677625. The cubic root of 80505779 is about 431.7930875692.

The spelling of 80505779 in words is "eighty million, five hundred five thousand, seven hundred seventy-nine".