78665033 has 2 divisors, whose sum is σ = 78665034. Its totient is φ = 78665032.

The previous prime is 78665029. The next prime is 78665047. The reversal of 78665033 is 33056687.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 76510009 + 2155024 = 8747^2 + 1468^2 .

It is a cyclic number.

It is not a de Polignac number, because 78665033 - 2² = 78665029 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (78665233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39332516 + 39332517.

It is an arithmetic number, because the mean of its divisors is an integer number (39332517).

Almost surely, 2^78665033 is an apocalyptic number.

It is an amenable number.

78665033 is a deficient number, since it is larger than the sum of its proper divisors (1).

78665033 is an equidigital number, since it uses as much as digits as its factorization.

78665033 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 90720, while the sum is 38.

The square root of 78665033 is about 8869.3310345257. The cubic root of 78665033 is about 428.4767320881.

The spelling of 78665033 in words is "seventy-eight million, six hundred sixty-five thousand, thirty-three".