491786111 has 2 divisors, whose sum is σ = 491786112. Its totient is φ = 491786110.

The previous prime is 491786083. The next prime is 491786117. The reversal of 491786111 is 111687194.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-491786111 is a prime.

It is a Sophie Germain prime.

It is equal to p_25945580 and since 491786111 and 25945580 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (491786117) 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, 245893055 + 245893056.

It is an arithmetic number, because the mean of its divisors is an integer number (245893056).

Almost surely, 2^491786111 is an apocalyptic number.

491786111 is a deficient number, since it is larger than the sum of its proper divisors (1).

491786111 is an equidigital number, since it uses as much as digits as its factorization.

491786111 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12096, while the sum is 38.

The square root of 491786111 is about 22176.2510582830. The cubic root of 491786111 is about 789.3302613027.

The spelling of 491786111 in words is "four hundred ninety-one million, seven hundred eighty-six thousand, one hundred eleven".