206121171611 has 4 divisors (see below), whose sum is σ = 206976446424. Its totient is φ = 205265896800.

The previous prime is 206121171601. The next prime is 206121171709. The reversal of 206121171611 is 116171121602.

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

It is a cyclic number.

It is not a de Polignac number, because 206121171611 - 2³⁴ = 188941302427 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (206121171601) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 427637045 + ... + 427637526.

It is an arithmetic number, because the mean of its divisors is an integer number (51744111606).

Almost surely, 2^206121171611 is an apocalyptic number.

206121171611 is a deficient number, since it is larger than the sum of its proper divisors (855274813).

206121171611 is an equidigital number, since it uses as much as digits as its factorization.

206121171611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 855274812.

The product of its (nonzero) digits is 1008, while the sum is 29.

The spelling of 206121171611 in words is "two hundred six billion, one hundred twenty-one million, one hundred seventy-one thousand, six hundred eleven".