78755441993 has 2 divisors, whose sum is σ = 78755441994. Its totient is φ = 78755441992.

The previous prime is 78755441953. The next prime is 78755442049. The reversal of 78755441993 is 39914455787.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 69609962569 + 9145479424 = 263837^2 + 95632^2 .

It is an emirp because it is prime and its reverse (39914455787) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78755441993 - 2²² = 78751247689 is a prime.

It is not a weakly prime, because it can be changed into another prime (78755441903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39377720996 + 39377720997.

It is an arithmetic number, because the mean of its divisors is an integer number (39377720997).

Almost surely, 2^78755441993 is an apocalyptic number.

It is an amenable number.

78755441993 is a deficient number, since it is larger than the sum of its proper divisors (1).

78755441993 is an equidigital number, since it uses as much as digits as its factorization.

78755441993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 38102400, while the sum is 62.

The spelling of 78755441993 in words is "seventy-eight billion, seven hundred fifty-five million, four hundred forty-one thousand, nine hundred ninety-three".