499678721 has 2 divisors, whose sum is σ = 499678722. Its totient is φ = 499678720.

The previous prime is 499678717. The next prime is 499678723. The reversal of 499678721 is 127876994.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 311028496 + 188650225 = 17636^2 + 13735^2 .

It is a cyclic number.

It is not a de Polignac number, because 499678721 - 2² = 499678717 is a prime.

Together with 499678723, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (499678723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 249839360 + 249839361.

It is an arithmetic number, because the mean of its divisors is an integer number (249839361).

Almost surely, 2^499678721 is an apocalyptic number.

It is an amenable number.

499678721 is a deficient number, since it is larger than the sum of its proper divisors (1).

499678721 is an equidigital number, since it uses as much as digits as its factorization.

499678721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1524096, while the sum is 53.

The square root of 499678721 is about 22353.4946037527. The cubic root of 499678721 is about 793.5304900187.

The spelling of 499678721 in words is "four hundred ninety-nine million, six hundred seventy-eight thousand, seven hundred twenty-one".