206665401 has 8 divisors (see below), whose sum is σ = 276758080. Its totient is φ = 137174832.

The previous prime is 206665367. The next prime is 206665421. The reversal of 206665401 is 104566602.

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

It is not a de Polignac number, because 206665401 - 2¹⁷ = 206534329 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (206665421) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 149725 + ... + 151098.

It is an arithmetic number, because the mean of its divisors is an integer number (34594760).

Almost surely, 2^206665401 is an apocalyptic number.

It is an amenable number.

206665401 is a deficient number, since it is larger than the sum of its proper divisors (70092679).

206665401 is a wasteful number, since it uses less digits than its factorization.

206665401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 301055.

The product of its (nonzero) digits is 8640, while the sum is 30.

The square root of 206665401 is about 14375.8617480831. The cubic root of 206665401 is about 591.2292679269.

The spelling of 206665401 in words is "two hundred six million, six hundred sixty-five thousand, four hundred one".