78816449 has 2 divisors, whose sum is σ = 78816450. Its totient is φ = 78816448.

The previous prime is 78816431. The next prime is 78816467. The reversal of 78816449 is 94461887.

It is a balanced prime because it is at equal distance from previous prime (78816431) and next prime (78816467).

It can be written as a sum of positive squares in only one way, i.e., 69422224 + 9394225 = 8332^2 + 3065^2 .

It is a cyclic number.

It is not a de Polignac number, because 78816449 - 2²⁴ = 62039233 is a prime.

It is not a weakly prime, because it can be changed into another prime (78816649) 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, 39408224 + 39408225.

It is an arithmetic number, because the mean of its divisors is an integer number (39408225).

Almost surely, 2^78816449 is an apocalyptic number.

It is an amenable number.

78816449 is a deficient number, since it is larger than the sum of its proper divisors (1).

78816449 is an equidigital number, since it uses as much as digits as its factorization.

78816449 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 387072, while the sum is 47.

The square root of 78816449 is about 8877.8628621983. The cubic root of 78816449 is about 428.7514693657.

The spelling of 78816449 in words is "seventy-eight million, eight hundred sixteen thousand, four hundred forty-nine".