71661379 has 2 divisors, whose sum is σ = 71661380. Its totient is φ = 71661378.

The previous prime is 71661377. The next prime is 71661413. The reversal of 71661379 is 97316617.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 71661379 - 2¹ = 71661377 is a prime.

Together with 71661377, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (71661371) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35830689 + 35830690.

It is an arithmetic number, because the mean of its divisors is an integer number (35830690).

Almost surely, 2^71661379 is an apocalyptic number.

71661379 is a deficient number, since it is larger than the sum of its proper divisors (1).

71661379 is an equidigital number, since it uses as much as digits as its factorization.

71661379 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 47628, while the sum is 40.

The square root of 71661379 is about 8465.3044245319. The cubic root of 71661379 is about 415.3635542617.

The spelling of 71661379 in words is "seventy-one million, six hundred sixty-one thousand, three hundred seventy-nine".