491613321 has 4 divisors (see below), whose sum is σ = 655484432. Its totient is φ = 327742212.

The previous prime is 491613271. The next prime is 491613337. The reversal of 491613321 is 123316194.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 491613321 - 2⁶ = 491613257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (491618321) 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, 81935551 + ... + 81935556.

It is an arithmetic number, because the mean of its divisors is an integer number (163871108).

Almost surely, 2^491613321 is an apocalyptic number.

It is an amenable number.

491613321 is a deficient number, since it is larger than the sum of its proper divisors (163871111).

491613321 is a wasteful number, since it uses less digits than its factorization.

491613321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163871110.

The product of its digits is 3888, while the sum is 30.

The square root of 491613321 is about 22172.3548816990. The cubic root of 491613321 is about 789.2378062365.

The spelling of 491613321 in words is "four hundred ninety-one million, six hundred thirteen thousand, three hundred twenty-one".