65681816 has 16 divisors (see below), whose sum is σ = 124889040. Its totient is φ = 32378080.

The previous prime is 65681797. The next prime is 65681821. The reversal of 65681816 is 61818656.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 57251 + ... + 58386.

It is an arithmetic number, because the mean of its divisors is an integer number (7805565).

Almost surely, 2^65681816 is an apocalyptic number.

It is an amenable number.

65681816 is a deficient number, since it is larger than the sum of its proper divisors (59207224).

65681816 is a wasteful number, since it uses less digits than its factorization.

65681816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115714 (or 115710 counting only the distinct ones).

The product of its digits is 69120, while the sum is 41.

The square root of 65681816 is about 8104.4318739811. The cubic root of 65681816 is about 403.4735324523.

The spelling of 65681816 in words is "sixty-five million, six hundred eighty-one thousand, eight hundred sixteen".