491111587 has 2 divisors, whose sum is σ = 491111588. Its totient is φ = 491111586.

The previous prime is 491111567. The next prime is 491111609. The reversal of 491111587 is 785111194.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-491111587 is a prime.

It is not a weakly prime, because it can be changed into another prime (491111567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245555793 + 245555794.

It is an arithmetic number, because the mean of its divisors is an integer number (245555794).

Almost surely, 2^491111587 is an apocalyptic number.

491111587 is a deficient number, since it is larger than the sum of its proper divisors (1).

491111587 is an equidigital number, since it uses as much as digits as its factorization.

491111587 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10080, while the sum is 37.

The square root of 491111587 is about 22161.0375885246. The cubic root of 491111587 is about 788.9692196501.

The spelling of 491111587 in words is "four hundred ninety-one million, one hundred eleven thousand, five hundred eighty-seven".