493721689 has 2 divisors, whose sum is σ = 493721690. Its totient is φ = 493721688.

The previous prime is 493721687. The next prime is 493721693. The reversal of 493721689 is 986127394.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 431185225 + 62536464 = 20765^2 + 7908^2 .

It is a cyclic number.

It is not a de Polignac number, because 493721689 - 2¹ = 493721687 is a prime.

It is a super-2 number, since 2×493721689² = 487522212378025442, which contains 22 as substring.

Together with 493721687, 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 (493721681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 246860844 + 246860845.

It is an arithmetic number, because the mean of its divisors is an integer number (246860845).

Almost surely, 2^493721689 is an apocalyptic number.

It is an amenable number.

493721689 is a deficient number, since it is larger than the sum of its proper divisors (1).

493721689 is an equidigital number, since it uses as much as digits as its factorization.

493721689 is an evil number, because the sum of its binary digits is even.

The product of its digits is 653184, while the sum is 49.

The square root of 493721689 is about 22219.8489868856. The cubic root of 493721689 is about 790.3644576969.

The spelling of 493721689 in words is "four hundred ninety-three million, seven hundred twenty-one thousand, six hundred eighty-nine".