81760247 has 2 divisors, whose sum is σ = 81760248. Its totient is φ = 81760246.

The previous prime is 81760201. The next prime is 81760271. The reversal of 81760247 is 74206718.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81760247 - 2⁶ = 81760183 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81760277) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40880123 + 40880124.

It is an arithmetic number, because the mean of its divisors is an integer number (40880124).

Almost surely, 2^81760247 is an apocalyptic number.

81760247 is a deficient number, since it is larger than the sum of its proper divisors (1).

81760247 is an equidigital number, since it uses as much as digits as its factorization.

81760247 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18816, while the sum is 35.

The square root of 81760247 is about 9042.1373026514. The cubic root of 81760247 is about 434.0243196039.

The spelling of 81760247 in words is "eighty-one million, seven hundred sixty thousand, two hundred forty-seven".