491355871 has 2 divisors, whose sum is σ = 491355872. Its totient is φ = 491355870.

The previous prime is 491355833. The next prime is 491355881. The reversal of 491355871 is 178553194.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 491355871 - 2²¹ = 489258719 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (491355881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245677935 + 245677936.

It is an arithmetic number, because the mean of its divisors is an integer number (245677936).

Almost surely, 2^491355871 is an apocalyptic number.

491355871 is a deficient number, since it is larger than the sum of its proper divisors (1).

491355871 is an equidigital number, since it uses as much as digits as its factorization.

491355871 is an evil number, because the sum of its binary digits is even.

The product of its digits is 151200, while the sum is 43.

The square root of 491355871 is about 22166.5484683565. The cubic root of 491355871 is about 789.1000117926.

The spelling of 491355871 in words is "four hundred ninety-one million, three hundred fifty-five thousand, eight hundred seventy-one".