23867561 has 4 divisors (see below), whose sum is σ = 23883972. Its totient is φ = 23851152.

The previous prime is 23867549. The next prime is 23867567. The reversal of 23867561 is 16576832.

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 11833600 + 12033961 = 3440^2 + 3469^2 .

It is a cyclic number.

It is not a de Polignac number, because 23867561 - 2¹⁰ = 23866537 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (23867567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5786 + ... + 9011.

It is an arithmetic number, because the mean of its divisors is an integer number (5970993).

Almost surely, 2^23867561 is an apocalyptic number.

It is an amenable number.

23867561 is a deficient number, since it is larger than the sum of its proper divisors (16411).

23867561 is a wasteful number, since it uses less digits than its factorization.

23867561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16410.

The product of its digits is 60480, while the sum is 38.

The square root of 23867561 is about 4885.4437874158. The cubic root of 23867561 is about 287.9183515010.

The spelling of 23867561 in words is "twenty-three million, eight hundred sixty-seven thousand, five hundred sixty-one".