216661541365604 has 12 divisors (see below), whose sum is σ = 379157848675200. Its totient is φ = 108330727458408.

The previous prime is 216661541365571. The next prime is 216661541365681. The reversal of 216661541365604 is 406563145166612.

It is a self number, because there is not a number n which added to its sum of digits gives 216661541365604.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2215457 + ... + 20933975.

It is an arithmetic number, because the mean of its divisors is an integer number (31596487389600).

Almost surely, 2^{216661541365604} is an apocalyptic number.

It is an amenable number.

216661541365604 is a deficient number, since it is larger than the sum of its proper divisors (162496307309596).

216661541365604 is a wasteful number, since it uses less digits than its factorization.

216661541365604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21612202 (or 21612200 counting only the distinct ones).

The product of its (nonzero) digits is 18662400, while the sum is 56.

The spelling of 216661541365604 in words is "two hundred sixteen trillion, six hundred sixty-one billion, five hundred forty-one million, three hundred sixty-five thousand, six hundred four".