239993999909 has 2 divisors, whose sum is σ = 239993999910. Its totient is φ = 239993999908.

The previous prime is 239993999893. The next prime is 239993999929. The reversal of 239993999909 is 909999399932.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 138456177409 + 101537822500 = 372097^2 + 318650^2 .

It is a cyclic number.

It is not a de Polignac number, because 239993999909 - 2⁴ = 239993999893 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (239993999929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 119996999954 + 119996999955.

It is an arithmetic number, because the mean of its divisors is an integer number (119996999955).

Almost surely, 2^239993999909 is an apocalyptic number.

It is an amenable number.

239993999909 is a deficient number, since it is larger than the sum of its proper divisors (1).

239993999909 is an equidigital number, since it uses as much as digits as its factorization.

239993999909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 774840978, while the sum is 80.

The spelling of 239993999909 in words is "two hundred thirty-nine billion, nine hundred ninety-three million, nine hundred ninety-nine thousand, nine hundred nine".