99991207 has 2 divisors, whose sum is σ = 99991208. Its totient is φ = 99991206.

The previous prime is 99991109. The next prime is 99991237. The reversal of 99991207 is 70219999.

It is a strong prime.

It is an emirp because it is prime and its reverse (70219999) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 99991207 - 2¹¹ = 99989159 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99991237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49995603 + 49995604.

It is an arithmetic number, because the mean of its divisors is an integer number (49995604).

Almost surely, 2^99991207 is an apocalyptic number.

99991207 is a deficient number, since it is larger than the sum of its proper divisors (1).

99991207 is an equidigital number, since it uses as much as digits as its factorization.

99991207 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 91854, while the sum is 46.

The square root of 99991207 is about 9999.5603403350. The cubic root of 99991207 is about 464.1452784656.

The spelling of 99991207 in words is "ninety-nine million, nine hundred ninety-one thousand, two hundred seven".