23686661 has 4 divisors (see below), whose sum is σ = 25080012. Its totient is φ = 22293312.

The previous prime is 23686657. The next prime is 23686667. The reversal of 23686661 is 16668632.

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 15880225 + 7806436 = 3985^2 + 2794^2 .

It is a cyclic number.

It is not a de Polignac number, because 23686661 - 2² = 23686657 is a prime.

It is a super-2 number, since 2×23686661² = 1122115818657842, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23686667) 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, 696650 + ... + 696683.

It is an arithmetic number, because the mean of its divisors is an integer number (6270003).

Almost surely, 2^23686661 is an apocalyptic number.

It is an amenable number.

23686661 is a deficient number, since it is larger than the sum of its proper divisors (1393351).

23686661 is a wasteful number, since it uses less digits than its factorization.

23686661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1393350.

The product of its digits is 62208, while the sum is 38.

The square root of 23686661 is about 4866.8943896493. The cubic root of 23686661 is about 287.1890970546.

The spelling of 23686661 in words is "twenty-three million, six hundred eighty-six thousand, six hundred sixty-one".