209094661 has 4 divisors (see below), whose sum is σ = 209192800. Its totient is φ = 208996524.

The previous prime is 209094649. The next prime is 209094667. The reversal of 209094661 is 166490902.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 166490902 = 2 ⋅83245451.

It is a cyclic number.

It is not a de Polignac number, because 209094661 - 2⁷ = 209094533 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 209094661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209094667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45801 + ... + 50158.

It is an arithmetic number, because the mean of its divisors is an integer number (52298200).

Almost surely, 2^209094661 is an apocalyptic number.

It is an amenable number.

209094661 is a deficient number, since it is larger than the sum of its proper divisors (98139).

209094661 is an equidigital number, since it uses as much as digits as its factorization.

209094661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98138.

The product of its (nonzero) digits is 23328, while the sum is 37.

The square root of 209094661 is about 14460.1058433194. The cubic root of 209094661 is about 593.5367959023.

The spelling of 209094661 in words is "two hundred nine million, ninety-four thousand, six hundred sixty-one".