999966439 has 2 divisors, whose sum is σ = 999966440. Its totient is φ = 999966438.

The previous prime is 999966427. The next prime is 999966449. The reversal of 999966439 is 934669999.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 999966439 - 2⁷ = 999966311 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999966449) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499983219 + 499983220.

It is an arithmetic number, because the mean of its divisors is an integer number (499983220).

Almost surely, 2^999966439 is an apocalyptic number.

999966439 is a deficient number, since it is larger than the sum of its proper divisors (1).

999966439 is an equidigital number, since it uses as much as digits as its factorization.

999966439 is an evil number, because the sum of its binary digits is even.

The product of its digits is 25509168, while the sum is 64.

The square root of 999966439 is about 31622.2459512287. The cubic root of 999966439 is about 999.9888128748.

It can be divided in two parts, 999966 and 439, that added together give a triangular number (1000405 = T₁₄₁₄).

The spelling of 999966439 in words is "nine hundred ninety-nine million, nine hundred sixty-six thousand, four hundred thirty-nine".