491193666 has 16 divisors (see below), whose sum is σ = 1091541600. Its totient is φ = 163731204.

The previous prime is 491193649. The next prime is 491193673. The reversal of 491193666 is 666391194.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4548036 + ... + 4548143.

It is an arithmetic number, because the mean of its divisors is an integer number (68221350).

Almost surely, 2^491193666 is an apocalyptic number.

491193666 is an abundant number, since it is smaller than the sum of its proper divisors (600347934).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

491193666 is a wasteful number, since it uses less digits than its factorization.

491193666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9096190 (or 9096184 counting only the distinct ones).

The product of its digits is 209952, while the sum is 45.

The square root of 491193666 is about 22162.8893874422. The cubic root of 491193666 is about 789.0131704202.

The spelling of 491193666 in words is "four hundred ninety-one million, one hundred ninety-three thousand, six hundred sixty-six".