81716699 has 2 divisors, whose sum is σ = 81716700. Its totient is φ = 81716698.

The previous prime is 81716689. The next prime is 81716749. The reversal of 81716699 is 99661718.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81716699 - 2⁸ = 81716443 is a prime.

It is not a weakly prime, because it can be changed into another prime (81716629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40858349 + 40858350.

It is an arithmetic number, because the mean of its divisors is an integer number (40858350).

Almost surely, 2^81716699 is an apocalyptic number.

81716699 is a deficient number, since it is larger than the sum of its proper divisors (1).

81716699 is an equidigital number, since it uses as much as digits as its factorization.

81716699 is an evil number, because the sum of its binary digits is even.

The product of its digits is 163296, while the sum is 47.

The square root of 81716699 is about 9039.7289229268. The cubic root of 81716699 is about 433.9472477241.

The spelling of 81716699 in words is "eighty-one million, seven hundred sixteen thousand, six hundred ninety-nine".