85217777 has 2 divisors, whose sum is σ = 85217778. Its totient is φ = 85217776.

The previous prime is 85217749. The next prime is 85217789. The reversal of 85217777 is 77771258.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 64705936 + 20511841 = 8044^2 + 4529^2 .

It is a cyclic number.

It is not a de Polignac number, because 85217777 - 2²² = 81023473 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (85217177) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42608888 + 42608889.

It is an arithmetic number, because the mean of its divisors is an integer number (42608889).

Almost surely, 2^85217777 is an apocalyptic number.

It is an amenable number.

85217777 is a deficient number, since it is larger than the sum of its proper divisors (1).

85217777 is an equidigital number, since it uses as much as digits as its factorization.

85217777 is an evil number, because the sum of its binary digits is even.

The product of its digits is 192080, while the sum is 44.

The square root of 85217777 is about 9231.3475181037. The cubic root of 85217777 is about 440.0581483068.

The spelling of 85217777 in words is "eighty-five million, two hundred seventeen thousand, seven hundred seventy-seven".