491646403 has 4 divisors (see below), whose sum is σ = 491693440. Its totient is φ = 491599368.

The previous prime is 491646383. The next prime is 491646427. The reversal of 491646403 is 304646194.

491646403 is a nontrivial binomial coefficient, being equal to C(31358, 2).

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 304646194 = 2 ⋅152323097.

It is a 3-Lehmer number, since φ(491646403) divides (491646403-1)³.

It is a cyclic number.

It is not a de Polignac number, because 491646403 - 2⁵ = 491646371 is a prime.

It is a deceptive number, since it divides R_491646402.

It is not an unprimeable number, because it can be changed into a prime (491646473) 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, 1 + ... + 31357.

It is an arithmetic number, because the mean of its divisors is an integer number (122923360).

Almost surely, 2^491646403 is an apocalyptic number.

491646403 is the 31357-th triangular number and also the 15679-th hexagonal number.

491646403 is the 10453-rd centered nonagonal number.

491646403 is a deficient number, since it is larger than the sum of its proper divisors (47037).

491646403 is a wasteful number, since it uses less digits than its factorization.

491646403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47036.

The product of its (nonzero) digits is 62208, while the sum is 37.

The square root of 491646403 is about 22173.1008882384. The cubic root of 491646403 is about 789.2555091603.

The spelling of 491646403 in words is "four hundred ninety-one million, six hundred forty-six thousand, four hundred three".