99778571 has 2 divisors, whose sum is σ = 99778572. Its totient is φ = 99778570.

The previous prime is 99778561. The next prime is 99778573. The reversal of 99778571 is 17587799.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 99778571 - 2⁶ = 99778507 is a prime.

Together with 99778573, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (99778573) 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, 49889285 + 49889286.

It is an arithmetic number, because the mean of its divisors is an integer number (49889286).

Almost surely, 2^99778571 is an apocalyptic number.

99778571 is a deficient number, since it is larger than the sum of its proper divisors (1).

99778571 is an equidigital number, since it uses as much as digits as its factorization.

99778571 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1111320, while the sum is 53.

The square root of 99778571 is about 9988.9224143548. The cubic root of 99778571 is about 463.8160360576.

The spelling of 99778571 in words is "ninety-nine million, seven hundred seventy-eight thousand, five hundred seventy-one".