65651601656666 has 16 divisors (see below), whose sum is σ = 103660602329760. Its totient is φ = 31098073502160.

The previous prime is 65651601656653. The next prime is 65651601656701. The reversal of 65651601656666 is 66665610615656.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28909640 + ... + 31097756.

It is an arithmetic number, because the mean of its divisors is an integer number (6478787645610).

Almost surely, 2^{65651601656666} is an apocalyptic number.

65651601656666 is a deficient number, since it is larger than the sum of its proper divisors (38009000673094).

65651601656666 is a wasteful number, since it uses less digits than its factorization.

65651601656666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2977709.

The product of its (nonzero) digits is 209952000, while the sum is 65.

The spelling of 65651601656666 in words is "sixty-five trillion, six hundred fifty-one billion, six hundred one million, six hundred fifty-six thousand, six hundred sixty-six".