516666391 has 2 divisors, whose sum is σ = 516666392. Its totient is φ = 516666390.

The previous prime is 516666383. The next prime is 516666439. The reversal of 516666391 is 193666615.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 516666391 - 2³ = 516666383 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (516666341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 258333195 + 258333196.

It is an arithmetic number, because the mean of its divisors is an integer number (258333196).

Almost surely, 2^516666391 is an apocalyptic number.

516666391 is a deficient number, since it is larger than the sum of its proper divisors (1).

516666391 is an equidigital number, since it uses as much as digits as its factorization.

516666391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 174960, while the sum is 43.

The square root of 516666391 is about 22730.2967644507. The cubic root of 516666391 is about 802.4230655115.

The spelling of 516666391 in words is "five hundred sixteen million, six hundred sixty-six thousand, three hundred ninety-one".