493721581 has 2 divisors, whose sum is σ = 493721582. Its totient is φ = 493721580.

The previous prime is 493721567. The next prime is 493721603. The reversal of 493721581 is 185127394.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 420619081 + 73102500 = 20509^2 + 8550^2 .

It is a cyclic number.

It is not a de Polignac number, because 493721581 - 2⁷ = 493721453 is a prime.

It is a super-2 number, since 2×493721581² = 487521999090279122, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (493721281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 246860790 + 246860791.

It is an arithmetic number, because the mean of its divisors is an integer number (246860791).

Almost surely, 2^493721581 is an apocalyptic number.

It is an amenable number.

493721581 is a deficient number, since it is larger than the sum of its proper divisors (1).

493721581 is an equidigital number, since it uses as much as digits as its factorization.

493721581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 60480, while the sum is 40.

The square root of 493721581 is about 22219.8465566259. The cubic root of 493721581 is about 790.3644000670.

The spelling of 493721581 in words is "four hundred ninety-three million, seven hundred twenty-one thousand, five hundred eighty-one".