81199203499 has 2 divisors, whose sum is σ = 81199203500. Its totient is φ = 81199203498.

The previous prime is 81199203439. The next prime is 81199203511. The reversal of 81199203499 is 99430299118.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81199203499 - 2¹¹ = 81199201451 is a prime.

It is not a weakly prime, because it can be changed into another prime (81199203439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40599601749 + 40599601750.

It is an arithmetic number, because the mean of its divisors is an integer number (40599601750).

Almost surely, 2^81199203499 is an apocalyptic number.

81199203499 is a deficient number, since it is larger than the sum of its proper divisors (1).

81199203499 is an equidigital number, since it uses as much as digits as its factorization.

81199203499 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1259712, while the sum is 55.

The spelling of 81199203499 in words is "eighty-one billion, one hundred ninety-nine million, two hundred three thousand, four hundred ninety-nine".