23666 has 4 divisors (see below), whose sum is σ = 35502. Its totient is φ = 11832.

The previous prime is 23663. The next prime is 23669. The reversal of 23666 is 66632.

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

It is an interprime number because it is at equal distance from previous prime (23663) and next prime (23669).

It can be written as a sum of positive squares in only one way, i.e., 14641 + 9025 = 121^2 + 95^2 .

It is a plaindrome in base 7 and base 10.

It is not an unprimeable number, because it can be changed into a prime (23663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5915 + ... + 5918.

2²³⁶⁶⁶ is an apocalyptic number.

23666 is a deficient number, since it is larger than the sum of its proper divisors (11836).

23666 is a wasteful number, since it uses less digits than its factorization.

23666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11835.

The product of its digits is 1296, while the sum is 23.

The square root of 23666 is about 153.8375766840. The cubic root of 23666 is about 28.7105571282.

It can be divided in two parts, 2366 and 6, that multiplied together give a triangular number (14196 = T₁₆₈).

The spelling of 23666 in words is "twenty-three thousand, six hundred sixty-six".