71087609 has 2 divisors, whose sum is σ = 71087610. Its totient is φ = 71087608.

The previous prime is 71087561. The next prime is 71087617. The reversal of 71087609 is 90678017.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 47224384 + 23863225 = 6872^2 + 4885^2 .

It is a cyclic number.

It is not a de Polignac number, because 71087609 - 2²⁰ = 70039033 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 (71087669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35543804 + 35543805.

It is an arithmetic number, because the mean of its divisors is an integer number (35543805).

Almost surely, 2^71087609 is an apocalyptic number.

It is an amenable number.

71087609 is a deficient number, since it is larger than the sum of its proper divisors (1).

71087609 is an equidigital number, since it uses as much as digits as its factorization.

71087609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21168, while the sum is 38.

The square root of 71087609 is about 8431.3468081914. The cubic root of 71087609 is about 414.2520208542.

The spelling of 71087609 in words is "seventy-one million, eighty-seven thousand, six hundred nine".