491707408139 has 4 divisors (see below), whose sum is σ = 491713894224. Its totient is φ = 491700922056.

The previous prime is 491707408121. The next prime is 491707408183. The reversal of 491707408139 is 931804707194.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 931804707194 = 2 ⋅465902353597.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-491707408139 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (491707408189) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3127967 + ... + 3281400.

It is an arithmetic number, because the mean of its divisors is an integer number (122928473556).

Almost surely, 2^491707408139 is an apocalyptic number.

491707408139 is a deficient number, since it is larger than the sum of its proper divisors (6486085).

491707408139 is an equidigital number, since it uses as much as digits as its factorization.

491707408139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6486084.

The product of its (nonzero) digits is 1524096, while the sum is 53.

The spelling of 491707408139 in words is "four hundred ninety-one billion, seven hundred seven million, four hundred eight thousand, one hundred thirty-nine".