78975289 has 2 divisors, whose sum is σ = 78975290. Its totient is φ = 78975288.

The previous prime is 78975287. The next prime is 78975301. The reversal of 78975289 is 98257987.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 78907689 + 67600 = 8883^2 + 260^2 .

It is a cyclic number.

It is not a de Polignac number, because 78975289 - 2¹ = 78975287 is a prime.

Together with 78975287, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78975283) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39487644 + 39487645.

It is an arithmetic number, because the mean of its divisors is an integer number (39487645).

Almost surely, 2^78975289 is an apocalyptic number.

It is an amenable number.

78975289 is a deficient number, since it is larger than the sum of its proper divisors (1).

78975289 is an equidigital number, since it uses as much as digits as its factorization.

78975289 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2540160, while the sum is 55.

The square root of 78975289 is about 8886.8042062375. The cubic root of 78975289 is about 429.0392992363.

The spelling of 78975289 in words is "seventy-eight million, nine hundred seventy-five thousand, two hundred eighty-nine".