81332099 has 2 divisors, whose sum is σ = 81332100. Its totient is φ = 81332098.

The previous prime is 81332081. The next prime is 81332101. The reversal of 81332099 is 99023318.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81332099 - 2²⁰ = 80283523 is a prime.

It is a super-2 number, since 2×81332099² = 13229820655491602, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 81332101, 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 (81332059) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40666049 + 40666050.

It is an arithmetic number, because the mean of its divisors is an integer number (40666050).

Almost surely, 2^81332099 is an apocalyptic number.

81332099 is a deficient number, since it is larger than the sum of its proper divisors (1).

81332099 is an equidigital number, since it uses as much as digits as its factorization.

81332099 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11664, while the sum is 35.

The square root of 81332099 is about 9018.4310719770. The cubic root of 81332099 is about 433.2653853356.

The spelling of 81332099 in words is "eighty-one million, three hundred thirty-two thousand, ninety-nine".