99891991933 has 2 divisors, whose sum is σ = 99891991934. Its totient is φ = 99891991932.

The previous prime is 99891991879. The next prime is 99891991943. The reversal of 99891991933 is 33919919899.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65845099609 + 34046892324 = 256603^2 + 184518^2 .

It is a cyclic number.

It is not a de Polignac number, because 99891991933 - 2⁹ = 99891991421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99891991943) 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, 49945995966 + 49945995967.

It is an arithmetic number, because the mean of its divisors is an integer number (49945995967).

Almost surely, 2^99891991933 is an apocalyptic number.

It is an amenable number.

99891991933 is a deficient number, since it is larger than the sum of its proper divisors (1).

99891991933 is an equidigital number, since it uses as much as digits as its factorization.

99891991933 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 38263752, while the sum is 70.

The spelling of 99891991933 in words is "ninety-nine billion, eight hundred ninety-one million, nine hundred ninety-one thousand, nine hundred thirty-three".