206505055178 has 8 divisors (see below), whose sum is σ = 309761728068. Its totient is φ = 103251145824.

The previous prime is 206505055151. The next prime is 206505055189. The reversal of 206505055178 is 871550505602.

It can be written as a sum of positive squares in 2 ways, for example, as 204080773009 + 2424282169 = 451753^2 + 49237^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×206505055178² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 492701 + ... + 809792.

Almost surely, 2^206505055178 is an apocalyptic number.

206505055178 is a deficient number, since it is larger than the sum of its proper divisors (103256672890).

206505055178 is a wasteful number, since it uses less digits than its factorization.

206505055178 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1381768.

The product of its (nonzero) digits is 420000, while the sum is 44.

The spelling of 206505055178 in words is "two hundred six billion, five hundred five million, fifty-five thousand, one hundred seventy-eight".