215166223550209 has 4 divisors (see below), whose sum is σ = 215167450799700. Its totient is φ = 215164996300720.

The previous prime is 215166223550147. The next prime is 215166223550303. The reversal of 215166223550209 is 902055322661512.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 176367775804609 + 38798447745600 = 13280353^2 + 6228840^2 .

It is a cyclic number.

It is not a de Polignac number, because 215166223550209 - 2¹¹ = 215166223548161 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215166223550909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 613361722 + ... + 613712419.

It is an arithmetic number, because the mean of its divisors is an integer number (53791862699925).

Almost surely, 2^{215166223550209} is an apocalyptic number.

It is an amenable number.

215166223550209 is a deficient number, since it is larger than the sum of its proper divisors (1227249491).

215166223550209 is a wasteful number, since it uses less digits than its factorization.

215166223550209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1227249490.

The product of its (nonzero) digits is 1944000, while the sum is 49.

The spelling of 215166223550209 in words is "two hundred fifteen trillion, one hundred sixty-six billion, two hundred twenty-three million, five hundred fifty thousand, two hundred nine".