491011111187 has 2 divisors, whose sum is σ = 491011111188. Its totient is φ = 491011111186.

The previous prime is 491011111181. The next prime is 491011111207. The reversal of 491011111187 is 781111110194.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 491011111187 - 2²⁰ = 491010062611 is a prime.

It is a super-2 number, since 2×491011111187² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (491011111181) 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, 245505555593 + 245505555594.

It is an arithmetic number, because the mean of its divisors is an integer number (245505555594).

Almost surely, 2^491011111187 is an apocalyptic number.

491011111187 is a deficient number, since it is larger than the sum of its proper divisors (1).

491011111187 is an equidigital number, since it uses as much as digits as its factorization.

491011111187 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2016, while the sum is 35.

The spelling of 491011111187 in words is "four hundred ninety-one billion, eleven million, one hundred eleven thousand, one hundred eighty-seven".