491243387 has 2 divisors, whose sum is σ = 491243388. Its totient is φ = 491243386.

The previous prime is 491243377. The next prime is 491243443. The reversal of 491243387 is 783342194.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 491243387 - 2¹² = 491239291 is a prime.

It is not a weakly prime, because it can be changed into another prime (491243377) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245621693 + 245621694.

It is an arithmetic number, because the mean of its divisors is an integer number (245621694).

Almost surely, 2^491243387 is an apocalyptic number.

491243387 is a deficient number, since it is larger than the sum of its proper divisors (1).

491243387 is an equidigital number, since it uses as much as digits as its factorization.

491243387 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 145152, while the sum is 41.

The square root of 491243387 is about 22164.0110765177. The cubic root of 491243387 is about 789.0397920991.

The spelling of 491243387 in words is "four hundred ninety-one million, two hundred forty-three thousand, three hundred eighty-seven".