23666661 has 10 divisors (see below), whose sum is σ = 35354022. Its totient is φ = 15777720.

The previous prime is 23666627. The next prime is 23666677. The reversal of 23666661 is 16666632.

It can be written as a sum of positive squares in only one way, i.e., 14630625 + 9036036 = 3825^2 + 3006^2 .

It is not a de Polignac number, because 23666661 - 2¹⁰ = 23665637 is a prime.

It is a super-2 number, since 2×23666661² = 1120221685777842, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23666561) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 146010 + ... + 146171.

Almost surely, 2^23666661 is an apocalyptic number.

It is an amenable number.

23666661 is a deficient number, since it is larger than the sum of its proper divisors (11687361).

23666661 is an equidigital number, since it uses as much as digits as its factorization.

23666661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 292193 (or 292184 counting only the distinct ones).

The product of its digits is 46656, while the sum is 36.

The square root of 23666661 is about 4864.8392573650. The cubic root of 23666661 is about 287.1082442446.

It can be divided in two parts, 2 and 3666661, that added together give a palindrome (3666663).

The spelling of 23666661 in words is "twenty-three million, six hundred sixty-six thousand, six hundred sixty-one".