239983409 has 2 divisors, whose sum is σ = 239983410. Its totient is φ = 239983408.

The previous prime is 239983399. The next prime is 239983421. The reversal of 239983409 is 904389932.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 239382784 + 600625 = 15472^2 + 775^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-239983409 is a prime.

It is a super-2 number, since 2×239983409² = 115184073190522562, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (239983459) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 119991704 + 119991705.

It is an arithmetic number, because the mean of its divisors is an integer number (119991705).

Almost surely, 2^239983409 is an apocalyptic number.

It is an amenable number.

239983409 is a deficient number, since it is larger than the sum of its proper divisors (1).

239983409 is an equidigital number, since it uses as much as digits as its factorization.

239983409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 419904, while the sum is 47.

The square root of 239983409 is about 15491.3979033527. The cubic root of 239983409 is about 621.4321808345.

The spelling of 239983409 in words is "two hundred thirty-nine million, nine hundred eighty-three thousand, four hundred nine".