78530399 has 2 divisors, whose sum is σ = 78530400. Its totient is φ = 78530398.

The previous prime is 78530377. The next prime is 78530437. The reversal of 78530399 is 99303587.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78530399 - 2⁸ = 78530143 is a prime.

It is a super-3 number, since 3×78530399³ (a number of 25 digits) contains 333 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78530329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39265199 + 39265200.

It is an arithmetic number, because the mean of its divisors is an integer number (39265200).

Almost surely, 2^78530399 is an apocalyptic number.

78530399 is a deficient number, since it is larger than the sum of its proper divisors (1).

78530399 is an equidigital number, since it uses as much as digits as its factorization.

78530399 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 204120, while the sum is 44.

The square root of 78530399 is about 8861.7379221008. The cubic root of 78530399 is about 428.2321487118.

The spelling of 78530399 in words is "seventy-eight million, five hundred thirty thousand, three hundred ninety-nine".