85220777 has 2 divisors, whose sum is σ = 85220778. Its totient is φ = 85220776.

The previous prime is 85220753. The next prime is 85220783. The reversal of 85220777 is 77702258.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 73633561 + 11587216 = 8581^2 + 3404^2 .

It is a cyclic number.

It is not a de Polignac number, because 85220777 - 2⁸ = 85220521 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 85220777.

It is not a weakly prime, because it can be changed into another prime (85220977) 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, 42610388 + 42610389.

It is an arithmetic number, because the mean of its divisors is an integer number (42610389).

Almost surely, 2^85220777 is an apocalyptic number.

It is an amenable number.

85220777 is a deficient number, since it is larger than the sum of its proper divisors (1).

85220777 is an equidigital number, since it uses as much as digits as its factorization.

85220777 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 54880, while the sum is 38.

The square root of 85220777 is about 9231.5100064941. The cubic root of 85220777 is about 440.0633121705.

The spelling of 85220777 in words is "eighty-five million, two hundred twenty thousand, seven hundred seventy-seven".