20612116566 has 24 divisors (see below), whose sum is σ = 46100218944. Its totient is φ = 6649069680.

The previous prime is 20612116561. The next prime is 20612116573. The reversal of 20612116566 is 66561121602.

20612116566 is a `hidden beast` number, since 2 + 0 + 61 + 21 + 16 + 566 = 666.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20612116566.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20612116561) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 18469081 + ... + 18470196.

It is an arithmetic number, because the mean of its divisors is an integer number (1920842456).

Almost surely, 2^20612116566 is an apocalyptic number.

20612116566 is an abundant number, since it is smaller than the sum of its proper divisors (25488102378).

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

20612116566 is a wasteful number, since it uses less digits than its factorization.

20612116566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36939316 (or 36939313 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The spelling of 20612116566 in words is "twenty billion, six hundred twelve million, one hundred sixteen thousand, five hundred sixty-six".