71917819 has 2 divisors, whose sum is σ = 71917820. Its totient is φ = 71917818.

The previous prime is 71917789. The next prime is 71917829. The reversal of 71917819 is 91871917.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 71917819 - 2¹¹ = 71915771 is a prime.

It is a super-2 number, since 2×71917819² = 10344345379433522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (71917829) 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, 35958909 + 35958910.

It is an arithmetic number, because the mean of its divisors is an integer number (35958910).

Almost surely, 2^71917819 is an apocalyptic number.

71917819 is a deficient number, since it is larger than the sum of its proper divisors (1).

71917819 is an equidigital number, since it uses as much as digits as its factorization.

71917819 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 31752, while the sum is 43.

The square root of 71917819 is about 8480.4374297556. The cubic root of 71917819 is about 415.8584234545.

The spelling of 71917819 in words is "seventy-one million, nine hundred seventeen thousand, eight hundred nineteen".