23561261 has 4 divisors (see below), whose sum is σ = 23884092. Its totient is φ = 23238432.

The previous prime is 23561257. The next prime is 23561281. The reversal of 23561261 is 16216532.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 19193161 + 4368100 = 4381^2 + 2090^2 .

It is a cyclic number.

It is not a de Polignac number, because 23561261 - 2² = 23561257 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 23561261.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23561231) 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, 161306 + ... + 161451.

It is an arithmetic number, because the mean of its divisors is an integer number (5971023).

Almost surely, 2^23561261 is an apocalyptic number.

It is an amenable number.

23561261 is a deficient number, since it is larger than the sum of its proper divisors (322831).

23561261 is an equidigital number, since it uses as much as digits as its factorization.

23561261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 322830.

The product of its digits is 2160, while the sum is 26.

The square root of 23561261 is about 4853.9943345661. The cubic root of 23561261 is about 286.6813956437.

Adding to 23561261 its reverse (16216532), we get a palindrome (39777793).

The spelling of 23561261 in words is "twenty-three million, five hundred sixty-one thousand, two hundred sixty-one".