78397399 has 2 divisors, whose sum is σ = 78397400. Its totient is φ = 78397398.

The previous prime is 78397379. The next prime is 78397483. The reversal of 78397399 is 99379387.

It is a weak prime.

It is an emirp because it is prime and its reverse (99379387) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78397399 - 2⁵ = 78397367 is a prime.

It is a super-2 number, since 2×78397399² = 12292304339930402, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78397379) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39198699 + 39198700.

It is an arithmetic number, because the mean of its divisors is an integer number (39198700).

Almost surely, 2^78397399 is an apocalyptic number.

78397399 is a deficient number, since it is larger than the sum of its proper divisors (1).

78397399 is an equidigital number, since it uses as much as digits as its factorization.

78397399 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2571912, while the sum is 55.

The square root of 78397399 is about 8854.2305707498. The cubic root of 78397399 is about 427.9902591168.

The spelling of 78397399 in words is "seventy-eight million, three hundred ninety-seven thousand, three hundred ninety-nine".