78489161 has 2 divisors, whose sum is σ = 78489162. Its totient is φ = 78489160.

The previous prime is 78489143. The next prime is 78489181. The reversal of 78489161 is 16198487.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 54479161 + 24010000 = 7381^2 + 4900^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78489161 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78489181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39244580 + 39244581.

It is an arithmetic number, because the mean of its divisors is an integer number (39244581).

Almost surely, 2^78489161 is an apocalyptic number.

It is an amenable number.

78489161 is a deficient number, since it is larger than the sum of its proper divisors (1).

78489161 is an equidigital number, since it uses as much as digits as its factorization.

78489161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 96768, while the sum is 44.

The square root of 78489161 is about 8859.4108720614. The cubic root of 78489161 is about 428.1571776195.

The spelling of 78489161 in words is "seventy-eight million, four hundred eighty-nine thousand, one hundred sixty-one".