491366993 has 24 divisors (see below), whose sum is σ = 550756800. Its totient is φ = 437845824.

The previous prime is 491366989. The next prime is 491367007. The reversal of 491366993 is 399663194.

It is not a de Polignac number, because 491366993 - 2² = 491366989 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (491366933) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1119068 + ... + 1119506.

It is an arithmetic number, because the mean of its divisors is an integer number (22948200).

Almost surely, 2^491366993 is an apocalyptic number.

It is an amenable number.

491366993 is a deficient number, since it is larger than the sum of its proper divisors (59389807).

491366993 is a wasteful number, since it uses less digits than its factorization.

491366993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 681 (or 668 counting only the distinct ones).

The product of its digits is 944784, while the sum is 50.

The square root of 491366993 is about 22166.7993404551. The cubic root of 491366993 is about 789.1059655928.

The spelling of 491366993 in words is "four hundred ninety-one million, three hundred sixty-six thousand, nine hundred ninety-three".