206007991 has 8 divisors (see below), whose sum is σ = 238754304. Its totient is φ = 174090840.

The previous prime is 206007961. The next prime is 206008009. The reversal of 206007991 is 199700602.

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

It is not a de Polignac number, because 206007991 - 2⁵ = 206007959 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (206007911) 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 7 ways as a sum of consecutive naturals, for example, 206755 + ... + 207748.

It is an arithmetic number, because the mean of its divisors is an integer number (29844288).

Almost surely, 2^206007991 is an apocalyptic number.

206007991 is a deficient number, since it is larger than the sum of its proper divisors (32746313).

206007991 is an equidigital number, since it uses as much as digits as its factorization.

206007991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 414581.

The product of its (nonzero) digits is 6804, while the sum is 34.

The square root of 206007991 is about 14352.9784713836. The cubic root of 206007991 is about 590.6016948934.

The spelling of 206007991 in words is "two hundred six million, seven thousand, nine hundred ninety-one".