491451173 has 2 divisors, whose sum is σ = 491451174. Its totient is φ = 491451172.

The previous prime is 491451167. The next prime is 491451187. The reversal of 491451173 is 371154194.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 289612324 + 201838849 = 17018^2 + 14207^2 .

It is a cyclic number.

It is not a de Polignac number, because 491451173 - 2⁶ = 491451109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (491451673) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245725586 + 245725587.

It is an arithmetic number, because the mean of its divisors is an integer number (245725587).

Almost surely, 2^491451173 is an apocalyptic number.

It is an amenable number.

491451173 is a deficient number, since it is larger than the sum of its proper divisors (1).

491451173 is an equidigital number, since it uses as much as digits as its factorization.

491451173 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15120, while the sum is 35.

The square root of 491451173 is about 22168.6980447657. The cubic root of 491451173 is about 789.1510256994.

The spelling of 491451173 in words is "four hundred ninety-one million, four hundred fifty-one thousand, one hundred seventy-three".