491642511 has 4 divisors (see below), whose sum is σ = 655523352. Its totient is φ = 327761672.

The previous prime is 491642477. The next prime is 491642531. The reversal of 491642511 is 115246194.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 491642511 - 2⁹ = 491641999 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491642531) 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 in 3 ways as a sum of consecutive naturals, for example, 81940416 + ... + 81940421.

It is an arithmetic number, because the mean of its divisors is an integer number (163880838).

Almost surely, 2^491642511 is an apocalyptic number.

491642511 is a deficient number, since it is larger than the sum of its proper divisors (163880841).

491642511 is a wasteful number, since it uses less digits than its factorization.

491642511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163880840.

The product of its digits is 8640, while the sum is 33.

The square root of 491642511 is about 22173.0131240659. The cubic root of 491642511 is about 789.2534265046.

The spelling of 491642511 in words is "four hundred ninety-one million, six hundred forty-two thousand, five hundred eleven".