23978449309 has 2 divisors, whose sum is σ = 23978449310. Its totient is φ = 23978449308.

The previous prime is 23978449303. The next prime is 23978449367. The reversal of 23978449309 is 90394487932.

It is an a-pointer prime, because the next prime (23978449367) can be obtained adding 23978449309 to its sum of digits (58).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20988765625 + 2989683684 = 144875^2 + 54678^2 .

It is a cyclic number.

It is not a de Polignac number, because 23978449309 - 2⁷ = 23978449181 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23978449303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11989224654 + 11989224655.

It is an arithmetic number, because the mean of its divisors is an integer number (11989224655).

Almost surely, 2^23978449309 is an apocalyptic number.

It is an amenable number.

23978449309 is a deficient number, since it is larger than the sum of its proper divisors (1).

23978449309 is an equidigital number, since it uses as much as digits as its factorization.

23978449309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11757312, while the sum is 58.

The spelling of 23978449309 in words is "twenty-three billion, nine hundred seventy-eight million, four hundred forty-nine thousand, three hundred nine".