491223149 has 2 divisors, whose sum is σ = 491223150. Its totient is φ = 491223148.

The previous prime is 491223127. The next prime is 491223181. The reversal of 491223149 is 941322194.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 470109124 + 21114025 = 21682^2 + 4595^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-491223149 is a prime.

It is a super-2 number, since 2×491223149² = 482600364226952402, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (491223119) 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, 245611574 + 245611575.

It is an arithmetic number, because the mean of its divisors is an integer number (245611575).

Almost surely, 2^491223149 is an apocalyptic number.

It is an amenable number.

491223149 is a deficient number, since it is larger than the sum of its proper divisors (1).

491223149 is an equidigital number, since it uses as much as digits as its factorization.

491223149 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 35.

The square root of 491223149 is about 22163.5545208795. The cubic root of 491223149 is about 789.0289564611.

The spelling of 491223149 in words is "four hundred ninety-one million, two hundred twenty-three thousand, one hundred forty-nine".