23621809 has 2 divisors, whose sum is σ = 23621810. Its totient is φ = 23621808.

The previous prime is 23621761. The next prime is 23621821. The reversal of 23621809 is 90812632.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23619600 + 2209 = 4860^2 + 47^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-23621809 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (23621839) 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 as a sum of consecutive naturals, namely, 11810904 + 11810905.

It is an arithmetic number, because the mean of its divisors is an integer number (11810905).

Almost surely, 2^23621809 is an apocalyptic number.

It is an amenable number.

23621809 is a deficient number, since it is larger than the sum of its proper divisors (1).

23621809 is an equidigital number, since it uses as much as digits as its factorization.

23621809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 23621809 is about 4860.2272580611. The cubic root of 23621809 is about 286.9267579698.

The spelling of 23621809 in words is "twenty-three million, six hundred twenty-one thousand, eight hundred nine".