99778867 has 2 divisors, whose sum is σ = 99778868. Its totient is φ = 99778866.

The previous prime is 99778841. The next prime is 99778907. The reversal of 99778867 is 76887799.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 99778867 - 2¹⁵ = 99746099 is a prime.

It is not a weakly prime, because it can be changed into another prime (99778267) 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, 49889433 + 49889434.

It is an arithmetic number, because the mean of its divisors is an integer number (49889434).

Almost surely, 2^99778867 is an apocalyptic number.

99778867 is a deficient number, since it is larger than the sum of its proper divisors (1).

99778867 is an equidigital number, since it uses as much as digits as its factorization.

99778867 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10668672, while the sum is 61.

The square root of 99778867 is about 9988.9372307568. The cubic root of 99778867 is about 463.8164947045.

The spelling of 99778867 in words is "ninety-nine million, seven hundred seventy-eight thousand, eight hundred sixty-seven".