78384617 has 2 divisors, whose sum is σ = 78384618. Its totient is φ = 78384616.

The previous prime is 78384613. The next prime is 78384641. The reversal of 78384617 is 71648387.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 70744921 + 7639696 = 8411^2 + 2764^2 .

It is a cyclic number.

It is not a de Polignac number, because 78384617 - 2² = 78384613 is a prime.

It is a super-2 number, since 2×78384617² = 12288296364473378, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78384613) 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, 39192308 + 39192309.

It is an arithmetic number, because the mean of its divisors is an integer number (39192309).

Almost surely, 2^78384617 is an apocalyptic number.

It is an amenable number.

78384617 is a deficient number, since it is larger than the sum of its proper divisors (1).

78384617 is an equidigital number, since it uses as much as digits as its factorization.

78384617 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 225792, while the sum is 44.

The square root of 78384617 is about 8853.5087394772. The cubic root of 78384617 is about 427.9669978484.

The spelling of 78384617 in words is "seventy-eight million, three hundred eighty-four thousand, six hundred seventeen".