71663866 has 8 divisors (see below), whose sum is σ = 108117684. Its totient is φ = 35624640.

The previous prime is 71663863. The next prime is 71663869. The reversal of 71663866 is 66836617.

It is an interprime number because it is at equal distance from previous prime (71663863) and next prime (71663869).

It can be written as a sum of positive squares in 2 ways, for example, as 62489025 + 9174841 = 7905^2 + 3029^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (71663863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 103215 + ... + 103906.

Almost surely, 2^71663866 is an apocalyptic number.

71663866 is a deficient number, since it is larger than the sum of its proper divisors (36453818).

71663866 is a wasteful number, since it uses less digits than its factorization.

71663866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 207296.

The product of its digits is 217728, while the sum is 43.

The square root of 71663866 is about 8465.4513169706. The cubic root of 71663866 is about 415.3683592544.

The spelling of 71663866 in words is "seventy-one million, six hundred sixty-three thousand, eight hundred sixty-six".