66550440205 has 8 divisors (see below), whose sum is σ = 79863991704. Its totient is φ = 53238043200.

The previous prime is 66550440179. The next prime is 66550440247. The reversal of 66550440205 is 50204405566.

It can be written as a sum of positive squares in 4 ways, for example, as 37124811684 + 29425628521 = 192678^2 + 171539^2 .

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

It is not a de Polignac number, because 66550440205 - 2³¹ = 64402956557 is a prime.

It is a super-2 number, since 2×66550440205² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 156286 + ... + 396895.

It is an arithmetic number, because the mean of its divisors is an integer number (9982998963).

Almost surely, 2^66550440205 is an apocalyptic number.

It is an amenable number.

66550440205 is a deficient number, since it is larger than the sum of its proper divisors (13313551499).

66550440205 is a wasteful number, since it uses less digits than its factorization.

66550440205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 577247.

The product of its (nonzero) digits is 144000, while the sum is 37.

The spelling of 66550440205 in words is "sixty-six billion, five hundred fifty million, four hundred forty thousand, two hundred five".