23821909 has 2 divisors, whose sum is σ = 23821910. Its totient is φ = 23821908.

The previous prime is 23821907. The next prime is 23821921. The reversal of 23821909 is 90912832.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20295025 + 3526884 = 4505^2 + 1878^2 .

It is a cyclic number.

It is not a de Polignac number, because 23821909 - 2¹ = 23821907 is a prime.

Together with 23821907, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23821907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11910954 + 11910955.

It is an arithmetic number, because the mean of its divisors is an integer number (11910955).

Almost surely, 2^23821909 is an apocalyptic number.

It is an amenable number.

23821909 is a deficient number, since it is larger than the sum of its proper divisors (1).

23821909 is an equidigital number, since it uses as much as digits as its factorization.

23821909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 23821909 is about 4880.7693041159. The cubic root of 23821909 is about 287.7346651188.

The spelling of 23821909 in words is "twenty-three million, eight hundred twenty-one thousand, nine hundred nine".