23105809 has 4 divisors (see below), whose sum is σ = 23144116. Its totient is φ = 23067504.

The previous prime is 23105807. The next prime is 23105833. The reversal of 23105809 is 90850132.

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 1203409 + 21902400 = 1097^2 + 4680^2 .

It is a cyclic number.

It is not a de Polignac number, because 23105809 - 2¹ = 23105807 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (23105801) 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, 18234 + ... + 19459.

It is an arithmetic number, because the mean of its divisors is an integer number (5786029).

Almost surely, 2^23105809 is an apocalyptic number.

It is an amenable number.

23105809 is a deficient number, since it is larger than the sum of its proper divisors (38307).

23105809 is an equidigital number, since it uses as much as digits as its factorization.

23105809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38306.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 23105809 is about 4806.8502160979. The cubic root of 23105809 is about 284.8221276481.

It can be divided in two parts, 2310 and 5809, that multiplied together give a triangular number (13418790 = T₅₁₈₀).

The spelling of 23105809 in words is "twenty-three million, one hundred five thousand, eight hundred nine".