71958078209 has 2 divisors, whose sum is σ = 71958078210. Its totient is φ = 71958078208.

The previous prime is 71958078163. The next prime is 71958078211. The reversal of 71958078209 is 90287085917.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 71380877584 + 577200625 = 267172^2 + 24025^2 .

It is a cyclic number.

It is not a de Polignac number, because 71958078209 - 2³² = 67663110913 is a prime.

Together with 71958078211, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (71958078229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35979039104 + 35979039105.

It is an arithmetic number, because the mean of its divisors is an integer number (35979039105).

Almost surely, 2^71958078209 is an apocalyptic number.

It is an amenable number.

71958078209 is a deficient number, since it is larger than the sum of its proper divisors (1).

71958078209 is an equidigital number, since it uses as much as digits as its factorization.

71958078209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2540160, while the sum is 56.

The spelling of 71958078209 in words is "seventy-one billion, nine hundred fifty-eight million, seventy-eight thousand, two hundred nine".