200661 has 8 divisors (see below), whose sum is σ = 269664. Its totient is φ = 132720.

The previous prime is 200657. The next prime is 200671. The reversal of 200661 is 166002.

200661 is a nontrivial binomial coefficient, being equal to C(634, 2).

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

It is not a de Polignac number, because 200661 - 2² = 200657 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 200661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (200671) 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 7 ways as a sum of consecutive naturals, for example, 475 + ... + 791.

It is an arithmetic number, because the mean of its divisors is an integer number (33708).

2²⁰⁰⁶⁶¹ is an apocalyptic number.

200661 is the 633-rd triangular number and also the 317-th hexagonal number.

It is an amenable number.

200661 is a deficient number, since it is larger than the sum of its proper divisors (69003).

200661 is a wasteful number, since it uses less digits than its factorization.

200661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 531.

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 200661 is about 447.9520063578. The cubic root of 200661 is about 58.5447097760.

Adding to 200661 its reverse (166002), we get a palindrome (366663).

It can be divided in two parts, 200 and 661, that added together give a triangular number (861 = T₄₁).

The spelling of 200661 in words is "two hundred thousand, six hundred sixty-one".