78869689 has 2 divisors, whose sum is σ = 78869690. Its totient is φ = 78869688.

The previous prime is 78869683. The next prime is 78869699. The reversal of 78869689 is 98696887.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 62805625 + 16064064 = 7925^2 + 4008^2 .

It is a cyclic number.

It is not a de Polignac number, because 78869689 - 2⁵ = 78869657 is a prime.

It is not a weakly prime, because it can be changed into another prime (78869683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39434844 + 39434845.

It is an arithmetic number, because the mean of its divisors is an integer number (39434845).

Almost surely, 2^78869689 is an apocalyptic number.

It is an amenable number.

78869689 is a deficient number, since it is larger than the sum of its proper divisors (1).

78869689 is an equidigital number, since it uses as much as digits as its factorization.

78869689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10450944, while the sum is 61.

The square root of 78869689 is about 8880.8608253930. The cubic root of 78869689 is about 428.8479872486.

The spelling of 78869689 in words is "seventy-eight million, eight hundred sixty-nine thousand, six hundred eighty-nine".