202661 has 2 divisors, whose sum is σ = 202662. Its totient is φ = 202660.

The previous prime is 202639. The next prime is 202667. The reversal of 202661 is 166202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 185761 + 16900 = 431^2 + 130^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-202661 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a plaindrome in base 9.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 202661.

It is not a weakly prime, because it can be changed into another prime (202667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 101330 + 101331.

It is an arithmetic number, because the mean of its divisors is an integer number (101331).

2²⁰²⁶⁶¹ is an apocalyptic number.

It is an amenable number.

202661 is a deficient number, since it is larger than the sum of its proper divisors (1).

202661 is an equidigital number, since it uses as much as digits as its factorization.

202661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 202661 is about 450.1788533461. The cubic root of 202661 is about 58.7385733021.

Adding to 202661 its reverse (166202), we get a palindrome (368863).

The spelling of 202661 in words is "two hundred two thousand, six hundred sixty-one".