78218219647 has 2 divisors, whose sum is σ = 78218219648. Its totient is φ = 78218219646.

The previous prime is 78218219621. The next prime is 78218219663. The reversal of 78218219647 is 74691281287.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78218219647 - 2²³ = 78209831039 is a prime.

It is a super-2 number, since 2×78218219647² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78218219617) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39109109823 + 39109109824.

It is an arithmetic number, because the mean of its divisors is an integer number (39109109824).

Almost surely, 2^78218219647 is an apocalyptic number.

78218219647 is a deficient number, since it is larger than the sum of its proper divisors (1).

78218219647 is an equidigital number, since it uses as much as digits as its factorization.

78218219647 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2709504, while the sum is 55.

The spelling of 78218219647 in words is "seventy-eight billion, two hundred eighteen million, two hundred nineteen thousand, six hundred forty-seven".