78784081 has 2 divisors, whose sum is σ = 78784082. Its totient is φ = 78784080.

The previous prime is 78784073. The next prime is 78784163. The reversal of 78784081 is 18048787.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 75690000 + 3094081 = 8700^2 + 1759^2 .

It is a cyclic number.

It is not a de Polignac number, because 78784081 - 2³ = 78784073 is a prime.

It is a super-2 number, since 2×78784081² = 12413862838029122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78784021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39392040 + 39392041.

It is an arithmetic number, because the mean of its divisors is an integer number (39392041).

Almost surely, 2^78784081 is an apocalyptic number.

It is an amenable number.

78784081 is a deficient number, since it is larger than the sum of its proper divisors (1).

78784081 is an equidigital number, since it uses as much as digits as its factorization.

78784081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 100352, while the sum is 43.

The square root of 78784081 is about 8876.0397137462. The cubic root of 78784081 is about 428.6927687267.

The spelling of 78784081 in words is "seventy-eight million, seven hundred eighty-four thousand, eighty-one".