23115509 has 2 divisors, whose sum is σ = 23115510. Its totient is φ = 23115508.

The previous prime is 23115503. The next prime is 23115539. The reversal of 23115509 is 90551132.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22829284 + 286225 = 4778^2 + 535^2 .

It is a cyclic number.

It is not a de Polignac number, because 23115509 - 2¹⁶ = 23049973 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23115503) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11557754 + 11557755.

It is an arithmetic number, because the mean of its divisors is an integer number (11557755).

Almost surely, 2^23115509 is an apocalyptic number.

It is an amenable number.

23115509 is a deficient number, since it is larger than the sum of its proper divisors (1).

23115509 is an equidigital number, since it uses as much as digits as its factorization.

23115509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1350, while the sum is 26.

The square root of 23115509 is about 4807.8590869534. The cubic root of 23115509 is about 284.8619789270.

The spelling of 23115509 in words is "twenty-three million, one hundred fifteen thousand, five hundred nine".