71768209 has 2 divisors, whose sum is σ = 71768210. Its totient is φ = 71768208.

The previous prime is 71768171. The next prime is 71768231. The reversal of 71768209 is 90286717.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 62331025 + 9437184 = 7895^2 + 3072^2 .

It is an emirp because it is prime and its reverse (90286717) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 71768209 - 2¹⁵ = 71735441 is a prime.

It is not a weakly prime, because it can be changed into another prime (71768239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35884104 + 35884105.

It is an arithmetic number, because the mean of its divisors is an integer number (35884105).

Almost surely, 2^71768209 is an apocalyptic number.

It is an amenable number.

71768209 is a deficient number, since it is larger than the sum of its proper divisors (1).

71768209 is an equidigital number, since it uses as much as digits as its factorization.

71768209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 42336, while the sum is 40.

The square root of 71768209 is about 8471.6119481478. The cubic root of 71768209 is about 415.5698543980.

The spelling of 71768209 in words is "seventy-one million, seven hundred sixty-eight thousand, two hundred nine".