78357289 has 2 divisors, whose sum is σ = 78357290. Its totient is φ = 78357288.

The previous prime is 78357281. The next prime is 78357317. The reversal of 78357289 is 98275387.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 57881664 + 20475625 = 7608^2 + 4525^2 .

It is a cyclic number.

It is not a de Polignac number, because 78357289 - 2³ = 78357281 is a prime.

It is a super-2 number, since 2×78357289² = 12279729478859042, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78357281) 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, 39178644 + 39178645.

It is an arithmetic number, because the mean of its divisors is an integer number (39178645).

Almost surely, 2^78357289 is an apocalyptic number.

It is an amenable number.

78357289 is a deficient number, since it is larger than the sum of its proper divisors (1).

78357289 is an equidigital number, since it uses as much as digits as its factorization.

78357289 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 846720, while the sum is 49.

The square root of 78357289 is about 8851.9652620195. The cubic root of 78357289 is about 427.9172566194.

The spelling of 78357289 in words is "seventy-eight million, three hundred fifty-seven thousand, two hundred eighty-nine".