78691390867 has 2 divisors, whose sum is σ = 78691390868. Its totient is φ = 78691390866.

The previous prime is 78691390801. The next prime is 78691390927. The reversal of 78691390867 is 76809319687.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78691390867 - 2¹¹ = 78691388819 is a prime.

It is a super-4 number, since 4×78691390867⁴ (a number of 45 digits) contains 4444 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 78691390799 and 78691390808.

It is not a weakly prime, because it can be changed into another prime (78691393867) 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, 39345695433 + 39345695434.

It is an arithmetic number, because the mean of its divisors is an integer number (39345695434).

Almost surely, 2^78691390867 is an apocalyptic number.

78691390867 is a deficient number, since it is larger than the sum of its proper divisors (1).

78691390867 is an equidigital number, since it uses as much as digits as its factorization.

78691390867 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27433728, while the sum is 64.

The spelling of 78691390867 in words is "seventy-eight billion, six hundred ninety-one million, three hundred ninety thousand, eight hundred sixty-seven".