99421999 has 2 divisors, whose sum is σ = 99422000. Its totient is φ = 99421998.

The previous prime is 99421979. The next prime is 99422017. The reversal of 99421999 is 99912499.

It is a strong prime.

It is an emirp because it is prime and its reverse (99912499) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 99421999 - 2⁷ = 99421871 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99421919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49710999 + 49711000.

It is an arithmetic number, because the mean of its divisors is an integer number (49711000).

Almost surely, 2^99421999 is an apocalyptic number.

99421999 is a deficient number, since it is larger than the sum of its proper divisors (1).

99421999 is an equidigital number, since it uses as much as digits as its factorization.

99421999 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 472392, while the sum is 52.

The square root of 99421999 is about 9971.0580682293. The cubic root of 99421999 is about 463.2628738270.

The spelling of 99421999 in words is "ninety-nine million, four hundred twenty-one thousand, nine hundred ninety-nine".