861627666305 has 16 divisors (see below), whose sum is σ = 1181822866560. Its totient is φ = 590749366272.

The previous prime is 861627666247. The next prime is 861627666311. The reversal of 861627666305 is 503666726168.

It is a cyclic number.

It is not a de Polignac number, because 861627666305 - 2¹² = 861627662209 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1428800 + ... + 1940289.

It is an arithmetic number, because the mean of its divisors is an integer number (73863929160).

Almost surely, 2^861627666305 is an apocalyptic number.

It is an amenable number.

861627666305 is a deficient number, since it is larger than the sum of its proper divisors (320195200255).

861627666305 is a wasteful number, since it uses less digits than its factorization.

861627666305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3376408.

The product of its (nonzero) digits is 13063680, while the sum is 56.

The spelling of 861627666305 in words is "eight hundred sixty-one billion, six hundred twenty-seven million, six hundred sixty-six thousand, three hundred five".