499997781 has 12 divisors (see below), whose sum is σ = 724530508. Its totient is φ = 332265024.

The previous prime is 499997731. The next prime is 499997783. The reversal of 499997781 is 187799994.

It can be written as a sum of positive squares in 2 ways, for example, as 4223025 + 495774756 = 2055^2 + 22266^2 .

It is not a de Polignac number, because 499997781 - 2⁹ = 499997269 is a prime.

It is a super-2 number, since 2×499997781² = 499995562009847922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (499997783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 85930 + ... + 91563.

Almost surely, 2^499997781 is an apocalyptic number.

It is an amenable number.

499997781 is a deficient number, since it is larger than the sum of its proper divisors (224532727).

499997781 is a wasteful number, since it uses less digits than its factorization.

499997781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177812 (or 177809 counting only the distinct ones).

The product of its digits is 10287648, while the sum is 63.

The square root of 499997781 is about 22360.6301565944. The cubic root of 499997781 is about 793.6993518347.

The spelling of 499997781 in words is "four hundred ninety-nine million, nine hundred ninety-seven thousand, seven hundred eighty-one".