20187256586166 has 72 divisors (see below), whose sum is σ = 45838882126440. Its totient is φ = 6585407237952.

The previous prime is 20187256586143. The next prime is 20187256586171. The reversal of 20187256586166 is 66168565278102.

20187256586166 is a `hidden beast` number, since 2 + 0 + 1 + 8 + 7 + 2 + 5 + 6 + 5 + 8 + 616 + 6 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1551785070 + ... + 1551798078.

It is an arithmetic number, because the mean of its divisors is an integer number (636651140645).

Almost surely, 2^{20187256586166} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20187256586166, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22919441063220).

20187256586166 is an abundant number, since it is smaller than the sum of its proper divisors (25651625540274).

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

20187256586166 is an frugal number, since it uses more digits than its factorization.

20187256586166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26123 (or 13061 counting only the distinct ones).

The product of its (nonzero) digits is 58060800, while the sum is 63.

The spelling of 20187256586166 in words is "twenty trillion, one hundred eighty-seven billion, two hundred fifty-six million, five hundred eighty-six thousand, one hundred sixty-six".