491356321 has 8 divisors (see below), whose sum is σ = 547642080. Its totient is φ = 438113088.

The previous prime is 491356303. The next prime is 491356339. The reversal of 491356321 is 123653194.

It is an interprime number because it is at equal distance from previous prime (491356303) and next prime (491356339).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 491356321 - 2²³ = 482967713 is a prime.

It is not an unprimeable number, because it can be changed into a prime (491356301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 760291 + ... + 760936.

It is an arithmetic number, because the mean of its divisors is an integer number (68455260).

Almost surely, 2^491356321 is an apocalyptic number.

It is an amenable number.

491356321 is a deficient number, since it is larger than the sum of its proper divisors (56285759).

491356321 is a wasteful number, since it uses less digits than its factorization.

491356321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1521263.

The product of its digits is 19440, while the sum is 34.

The square root of 491356321 is about 22166.5586187843. The cubic root of 491356321 is about 789.1002526872.

The spelling of 491356321 in words is "four hundred ninety-one million, three hundred fifty-six thousand, three hundred twenty-one".