206566021620 has 144 divisors (see below), whose sum is σ = 716215893120. Its totient is φ = 47207155968.

The previous prime is 206566021601. The next prime is 206566021621. The reversal of 206566021620 is 26120665602.

206566021620 is a `hidden beast` number, since 2 + 0 + 6 + 5 + 6 + 6 + 0 + 21 + 620 = 666.

206566021620 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (206566021621) 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 47 ways as a sum of consecutive naturals, for example, 10943751 + ... + 10962609.

It is an arithmetic number, because the mean of its divisors is an integer number (4973721480).

Almost surely, 2^206566021620 is an apocalyptic number.

206566021620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

206566021620 is an abundant number, since it is smaller than the sum of its proper divisors (509649871500).

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

206566021620 is a wasteful number, since it uses less digits than its factorization.

206566021620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27574 (or 27569 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The spelling of 206566021620 in words is "two hundred six billion, five hundred sixty-six million, twenty-one thousand, six hundred twenty".