78043993 has 2 divisors, whose sum is σ = 78043994. Its totient is φ = 78043992.

The previous prime is 78043967. The next prime is 78043997. The reversal of 78043993 is 39934087.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 58798224 + 19245769 = 7668^2 + 4387^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78043993 is a prime.

It is not a weakly prime, because it can be changed into another prime (78043997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39021996 + 39021997.

It is an arithmetic number, because the mean of its divisors is an integer number (39021997).

Almost surely, 2^78043993 is an apocalyptic number.

It is an amenable number.

78043993 is a deficient number, since it is larger than the sum of its proper divisors (1).

78043993 is an equidigital number, since it uses as much as digits as its factorization.

78043993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 163296, while the sum is 43.

The square root of 78043993 is about 8834.2511284206. The cubic root of 78043993 is about 427.3461808817.

The spelling of 78043993 in words is "seventy-eight million, forty-three thousand, nine hundred ninety-three".