81352247 has 2 divisors, whose sum is σ = 81352248. Its totient is φ = 81352246.

The previous prime is 81352217. The next prime is 81352261. The reversal of 81352247 is 74225318.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81352247 - 2¹² = 81348151 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81352217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40676123 + 40676124.

It is an arithmetic number, because the mean of its divisors is an integer number (40676124).

Almost surely, 2^81352247 is an apocalyptic number.

81352247 is a deficient number, since it is larger than the sum of its proper divisors (1).

81352247 is an equidigital number, since it uses as much as digits as its factorization.

81352247 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13440, while the sum is 32.

The square root of 81352247 is about 9019.5480485443. The cubic root of 81352247 is about 433.3011592812.

The spelling of 81352247 in words is "eighty-one million, three hundred fifty-two thousand, two hundred forty-seven".