491172853 has 2 divisors, whose sum is σ = 491172854. Its totient is φ = 491172852.

The previous prime is 491172809. The next prime is 491172859. The reversal of 491172853 is 358271194.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 485012529 + 6160324 = 22023^2 + 2482^2 .

It is a cyclic number.

It is not a de Polignac number, because 491172853 - 2¹⁷ = 491041781 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (491172859) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245586426 + 245586427.

It is an arithmetic number, because the mean of its divisors is an integer number (245586427).

Almost surely, 2^491172853 is an apocalyptic number.

It is an amenable number.

491172853 is a deficient number, since it is larger than the sum of its proper divisors (1).

491172853 is an equidigital number, since it uses as much as digits as its factorization.

491172853 is an evil number, because the sum of its binary digits is even.

The product of its digits is 60480, while the sum is 40.

The square root of 491172853 is about 22162.4198362904. The cubic root of 491172853 is about 789.0020261647.

The spelling of 491172853 in words is "four hundred ninety-one million, one hundred seventy-two thousand, eight hundred fifty-three".