549335981 has 2 divisors, whose sum is σ = 549335982. Its totient is φ = 549335980.

The previous prime is 549335947. The next prime is 549335987. The reversal of 549335981 is 189533945.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 539818756 + 9517225 = 23234^2 + 3085^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-549335981 is a prime.

It is a super-2 number, since 2×549335981² = 603540040042464722, 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 (549335987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 274667990 + 274667991.

It is an arithmetic number, because the mean of its divisors is an integer number (274667991).

Almost surely, 2^549335981 is an apocalyptic number.

It is an amenable number.

549335981 is a deficient number, since it is larger than the sum of its proper divisors (1).

549335981 is an equidigital number, since it uses as much as digits as its factorization.

549335981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 583200, while the sum is 47.

The square root of 549335981 is about 23437.9175909465. The cubic root of 549335981 is about 818.9914136425.

The spelling of 549335981 in words is "five hundred forty-nine million, three hundred thirty-five thousand, nine hundred eighty-one".