23665681 has 8 divisors (see below), whose sum is σ = 26175464. Its totient is φ = 21254400.

The previous prime is 23665657. The next prime is 23665687. The reversal of 23665681 is 18656632.

It can be written as a sum of positive squares in 4 ways, for example, as 625681 + 23040000 = 791^2 + 4800^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 23665681 - 2⁷ = 23665553 is a prime.

It is a super-2 number, since 2×23665681² = 1120128914387522, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (37).

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 23665681.

It is not an unprimeable number, because it can be changed into a prime (23665687) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24120 + ... + 25081.

It is an arithmetic number, because the mean of its divisors is an integer number (3271933).

Almost surely, 2^23665681 is an apocalyptic number.

It is an amenable number.

23665681 is a deficient number, since it is larger than the sum of its proper divisors (2509783).

23665681 is a wasteful number, since it uses less digits than its factorization.

23665681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49251.

The product of its digits is 51840, while the sum is 37.

The square root of 23665681 is about 4864.7385335699. The cubic root of 23665681 is about 287.1042812864.

The spelling of 23665681 in words is "twenty-three million, six hundred sixty-five thousand, six hundred eighty-one".