491931766 has 4 divisors (see below), whose sum is σ = 737897652. Its totient is φ = 245965882.

The previous prime is 491931757. The next prime is 491931809. The reversal of 491931766 is 667139194.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 122982940 + ... + 122982943.

It is an arithmetic number, because the mean of its divisors is an integer number (184474413).

Almost surely, 2^491931766 is an apocalyptic number.

491931766 is a deficient number, since it is larger than the sum of its proper divisors (245965886).

491931766 is a wasteful number, since it uses less digits than its factorization.

491931766 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 245965885.

The product of its digits is 244944, while the sum is 46.

The square root of 491931766 is about 22179.5348463398. The cubic root of 491931766 is about 789.4081803737.

The spelling of 491931766 in words is "four hundred ninety-one million, nine hundred thirty-one thousand, seven hundred sixty-six".