491193665 has 32 divisors (see below), whose sum is σ = 642453120. Its totient is φ = 359117824.

The previous prime is 491193649. The next prime is 491193673. The reversal of 491193665 is 566391194.

It is not a de Polignac number, because 491193665 - 2⁴ = 491193649 is a prime.

It is a super-2 number, since 2×491193665² = 482542433072264450, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 481526 + ... + 482544.

It is an arithmetic number, because the mean of its divisors is an integer number (20076660).

Almost surely, 2^491193665 is an apocalyptic number.

It is an amenable number.

491193665 is a deficient number, since it is larger than the sum of its proper divisors (151259455).

491193665 is a wasteful number, since it uses less digits than its factorization.

491193665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1201.

The product of its digits is 174960, while the sum is 44.

The square root of 491193665 is about 22162.8893648820. The cubic root of 491193665 is about 789.0131698847.

The spelling of 491193665 in words is "four hundred ninety-one million, one hundred ninety-three thousand, six hundred sixty-five".