491686503 has 64 divisors (see below), whose sum is σ = 890265600. Its totient is φ = 233573760.

The previous prime is 491686493. The next prime is 491686549. The reversal of 491686503 is 305686194.

It is not a de Polignac number, because 491686503 - 2¹⁶ = 491620967 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491686703) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 125350 + ... + 129212.

It is an arithmetic number, because the mean of its divisors is an integer number (13910400).

Almost surely, 2^491686503 is an apocalyptic number.

491686503 is a deficient number, since it is larger than the sum of its proper divisors (398579097).

491686503 is a wasteful number, since it uses less digits than its factorization.

491686503 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3932.

The product of its (nonzero) digits is 155520, while the sum is 42.

The square root of 491686503 is about 22174.0051186068. The cubic root of 491686503 is about 789.2769665094.

It can be divided in two parts, 4916 and 86503, that added together give a palindrome (91419).

The spelling of 491686503 in words is "four hundred ninety-one million, six hundred eighty-six thousand, five hundred three".