78205019 has 2 divisors, whose sum is σ = 78205020. Its totient is φ = 78205018.

The previous prime is 78204983. The next prime is 78205021. The reversal of 78205019 is 91050287.

It is a strong prime.

It is an emirp because it is prime and its reverse (91050287) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78205019 is a prime.

It is a super-2 number, since 2×78205019² = 12232049993580722, which contains 22 as substring.

Together with 78205021, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78205319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39102509 + 39102510.

It is an arithmetic number, because the mean of its divisors is an integer number (39102510).

Almost surely, 2^78205019 is an apocalyptic number.

78205019 is a deficient number, since it is larger than the sum of its proper divisors (1).

78205019 is an equidigital number, since it uses as much as digits as its factorization.

78205019 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5040, while the sum is 32.

The square root of 78205019 is about 8843.3601645528. The cubic root of 78205019 is about 427.6398894702.

The spelling of 78205019 in words is "seventy-eight million, two hundred five thousand, nineteen".