99779081 has 2 divisors, whose sum is σ = 99779082. Its totient is φ = 99779080.

The previous prime is 99779077. The next prime is 99779131. The reversal of 99779081 is 18097799.

It is an a-pointer prime, because the next prime (99779131) can be obtained adding 99779081 to its sum of digits (50).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 98327056 + 1452025 = 9916^2 + 1205^2 .

It is a cyclic number.

It is not a de Polignac number, because 99779081 - 2² = 99779077 is a prime.

It is a super-2 number, since 2×99779081² = 19911730010409122, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (99779021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49889540 + 49889541.

It is an arithmetic number, because the mean of its divisors is an integer number (49889541).

Almost surely, 2^99779081 is an apocalyptic number.

It is an amenable number.

99779081 is a deficient number, since it is larger than the sum of its proper divisors (1).

99779081 is an equidigital number, since it uses as much as digits as its factorization.

99779081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 285768, while the sum is 50.

The square root of 99779081 is about 9988.9479426014. The cubic root of 99779081 is about 463.8168262933.

The spelling of 99779081 in words is "ninety-nine million, seven hundred seventy-nine thousand, eighty-one".