491501687 has 2 divisors, whose sum is σ = 491501688. Its totient is φ = 491501686.

The previous prime is 491501677. The next prime is 491501693. The reversal of 491501687 is 786105194.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 491501687 - 2⁸ = 491501431 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (491501677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245750843 + 245750844.

It is an arithmetic number, because the mean of its divisors is an integer number (245750844).

Almost surely, 2^491501687 is an apocalyptic number.

491501687 is a deficient number, since it is larger than the sum of its proper divisors (1).

491501687 is an equidigital number, since it uses as much as digits as its factorization.

491501687 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 60480, while the sum is 41.

The square root of 491501687 is about 22169.8373246174. The cubic root of 491501687 is about 789.1780625048.

The spelling of 491501687 in words is "four hundred ninety-one million, five hundred one thousand, six hundred eighty-seven".