78869899 has 2 divisors, whose sum is σ = 78869900. Its totient is φ = 78869898.

The previous prime is 78869873. The next prime is 78869927. The reversal of 78869899 is 99896887.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78869899 - 2⁷ = 78869771 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 78869899.

It is not a weakly prime, because it can be changed into another prime (78869839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39434949 + 39434950.

It is an arithmetic number, because the mean of its divisors is an integer number (39434950).

Almost surely, 2^78869899 is an apocalyptic number.

78869899 is a deficient number, since it is larger than the sum of its proper divisors (1).

78869899 is an equidigital number, since it uses as much as digits as its factorization.

78869899 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15676416, while the sum is 64.

The square root of 78869899 is about 8880.8726485633. The cubic root of 78869899 is about 428.8483678680.

The spelling of 78869899 in words is "seventy-eight million, eight hundred sixty-nine thousand, eight hundred ninety-nine".