80777729 has 2 divisors, whose sum is σ = 80777730. Its totient is φ = 80777728.

The previous prime is 80777717. The next prime is 80777773. The reversal of 80777729 is 92777708.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 76038400 + 4739329 = 8720^2 + 2177^2 .

It is a cyclic number.

It is not a de Polignac number, because 80777729 - 2⁴ = 80777713 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (80777629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40388864 + 40388865.

It is an arithmetic number, because the mean of its divisors is an integer number (40388865).

Almost surely, 2^80777729 is an apocalyptic number.

It is an amenable number.

80777729 is a deficient number, since it is larger than the sum of its proper divisors (1).

80777729 is an equidigital number, since it uses as much as digits as its factorization.

80777729 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 345744, while the sum is 47.

The square root of 80777729 is about 8987.6431282066. The cubic root of 80777729 is about 432.2787427882.

The spelling of 80777729 in words is "eighty million, seven hundred seventy-seven thousand, seven hundred twenty-nine".