23305661 has 4 divisors (see below), whose sum is σ = 23345952. Its totient is φ = 23265372.

The previous prime is 23305651. The next prime is 23305663. The reversal of 23305661 is 16650332.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-23305661 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 23305661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23305663) 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, 19265 + ... + 20438.

It is an arithmetic number, because the mean of its divisors is an integer number (5836488).

Almost surely, 2^23305661 is an apocalyptic number.

It is an amenable number.

23305661 is a deficient number, since it is larger than the sum of its proper divisors (40291).

23305661 is an equidigital number, since it uses as much as digits as its factorization.

23305661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40290.

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

The square root of 23305661 is about 4827.5937070139. The cubic root of 23305661 is about 285.6409540731.

Adding to 23305661 its reverse (16650332), we get a palindrome (39955993).

The spelling of 23305661 in words is "twenty-three million, three hundred five thousand, six hundred sixty-one".