78324217 has 2 divisors, whose sum is σ = 78324218. Its totient is φ = 78324216.

The previous prime is 78324179. The next prime is 78324241. The reversal of 78324217 is 71242387.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 69538921 + 8785296 = 8339^2 + 2964^2 .

It is a cyclic number.

It is not a de Polignac number, because 78324217 - 2¹¹ = 78322169 is a prime.

It is a super-2 number, since 2×78324217² = 12269365937326178, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78324017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39162108 + 39162109.

It is an arithmetic number, because the mean of its divisors is an integer number (39162109).

Almost surely, 2^78324217 is an apocalyptic number.

It is an amenable number.

78324217 is a deficient number, since it is larger than the sum of its proper divisors (1).

78324217 is an equidigital number, since it uses as much as digits as its factorization.

78324217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18816, while the sum is 34.

The square root of 78324217 is about 8850.0970051181. The cubic root of 78324217 is about 427.8570449437.

The spelling of 78324217 in words is "seventy-eight million, three hundred twenty-four thousand, two hundred seventeen".