71663868 has 36 divisors (see below), whose sum is σ = 183193920. Its totient is φ = 23618496.

The previous prime is 71663863. The next prime is 71663869. The reversal of 71663868 is 86836617.

71663868 is a `hidden beast` number, since 7 + 1 + 6 + 638 + 6 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

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 11 ways as a sum of consecutive naturals, for example, 7980 + ... + 14387.

It is an arithmetic number, because the mean of its divisors is an integer number (5088720).

Almost surely, 2^71663868 is an apocalyptic number.

It is an amenable number.

71663868 is an abundant number, since it is smaller than the sum of its proper divisors (111530052).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

71663868 is a wasteful number, since it uses less digits than its factorization.

71663868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22466 (or 22461 counting only the distinct ones).

The product of its digits is 290304, while the sum is 45.

The square root of 71663868 is about 8465.4514350978. The cubic root of 71663868 is about 415.3683631185.

The spelling of 71663868 in words is "seventy-one million, six hundred sixty-three thousand, eight hundred sixty-eight".