203530661 has 2 divisors, whose sum is σ = 203530662. Its totient is φ = 203530660.

The previous prime is 203530651. The next prime is 203530667. The reversal of 203530661 is 166035302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 193488100 + 10042561 = 13910^2 + 3169^2 .

It is a cyclic number.

It is not a de Polignac number, because 203530661 - 2⁶ = 203530597 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 203530661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (203530667) 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 as a sum of consecutive naturals, namely, 101765330 + 101765331.

It is an arithmetic number, because the mean of its divisors is an integer number (101765331).

Almost surely, 2^203530661 is an apocalyptic number.

It is an amenable number.

203530661 is a deficient number, since it is larger than the sum of its proper divisors (1).

203530661 is an equidigital number, since it uses as much as digits as its factorization.

203530661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3240, while the sum is 26.

The square root of 203530661 is about 14266.4172447044. The cubic root of 203530661 is about 588.2247326521.

Adding to 203530661 its reverse (166035302), we get a palindrome (369565963).

The spelling of 203530661 in words is "two hundred three million, five hundred thirty thousand, six hundred sixty-one".