82778317 has 2 divisors, whose sum is σ = 82778318. Its totient is φ = 82778316.

The previous prime is 82778309. The next prime is 82778323. The reversal of 82778317 is 71387728.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 45981961 + 36796356 = 6781^2 + 6066^2 .

It is a cyclic number.

It is not a de Polignac number, because 82778317 - 2³ = 82778309 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (82778347) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41389158 + 41389159.

It is an arithmetic number, because the mean of its divisors is an integer number (41389159).

Almost surely, 2^82778317 is an apocalyptic number.

It is an amenable number.

82778317 is a deficient number, since it is larger than the sum of its proper divisors (1).

82778317 is an equidigital number, since it uses as much as digits as its factorization.

82778317 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 131712, while the sum is 43.

The square root of 82778317 is about 9098.2590092830. The cubic root of 82778317 is about 435.8183687105.

The spelling of 82778317 in words is "eighty-two million, seven hundred seventy-eight thousand, three hundred seventeen".