71370809 has 2 divisors, whose sum is σ = 71370810. Its totient is φ = 71370808.

The previous prime is 71370797. The next prime is 71370839. The reversal of 71370809 is 90807317.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60295225 + 11075584 = 7765^2 + 3328^2 .

It is an emirp because it is prime and its reverse (90807317) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71370809 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (71370839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35685404 + 35685405.

It is an arithmetic number, because the mean of its divisors is an integer number (35685405).

Almost surely, 2^71370809 is an apocalyptic number.

It is an amenable number.

71370809 is a deficient number, since it is larger than the sum of its proper divisors (1).

71370809 is an equidigital number, since it uses as much as digits as its factorization.

71370809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10584, while the sum is 35.

The square root of 71370809 is about 8448.1245847821. The cubic root of 71370809 is about 414.8013933310.

The spelling of 71370809 in words is "seventy-one million, three hundred seventy thousand, eight hundred nine".