202561 has 4 divisors (see below), whose sum is σ = 211392. Its totient is φ = 193732.

The previous prime is 202549. The next prime is 202567. The reversal of 202561 is 165202.

It is a happy number.

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: 165202 = 2 ⋅82601.

It is a cyclic number.

It is not a de Polignac number, because 202561 - 2⁵ = 202529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (202567) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4381 + ... + 4426.

It is an arithmetic number, because the mean of its divisors is an integer number (52848).

2²⁰²⁵⁶¹ is an apocalyptic number.

It is an amenable number.

202561 is a deficient number, since it is larger than the sum of its proper divisors (8831).

202561 is an equidigital number, since it uses as much as digits as its factorization.

202561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8830.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 202561 is about 450.0677726743. The cubic root of 202561 is about 58.7289104929.

Adding to 202561 its reverse (165202), we get a palindrome (367763).

The spelling of 202561 in words is "two hundred two thousand, five hundred sixty-one".