78139881516187 has 2 divisors, whose sum is σ = 78139881516188. Its totient is φ = 78139881516186.

The previous prime is 78139881516181. The next prime is 78139881516289. The reversal of 78139881516187 is 78161518893187.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78139881516187 is a prime.

It is a super-2 number, since 2×78139881516187² (a number of 29 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78139881516181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39069940758093 + 39069940758094.

It is an arithmetic number, because the mean of its divisors is an integer number (39069940758094).

Almost surely, 2^{78139881516187} is an apocalyptic number.

78139881516187 is a deficient number, since it is larger than the sum of its proper divisors (1).

78139881516187 is an equidigital number, since it uses as much as digits as its factorization.

78139881516187 is an evil number, because the sum of its binary digits is even.

The product of its digits is 162570240, while the sum is 73.

The spelling of 78139881516187 in words is "seventy-eight trillion, one hundred thirty-nine billion, eight hundred eighty-one million, five hundred sixteen thousand, one hundred eighty-seven".