16549081 has 2 divisors, whose sum is σ = 16549082. Its totient is φ = 16549080.

The previous prime is 16549069. The next prime is 16549129. The reversal of 16549081 is 18094561.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16000000 + 549081 = 4000^2 + 741^2 .

It is an emirp because it is prime and its reverse (18094561) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16549081 - 2¹³ = 16540889 is a prime.

It is a super-2 number, since 2×16549081² = 547744163889122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (16549021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8274540 + 8274541.

It is an arithmetic number, because the mean of its divisors is an integer number (8274541).

Almost surely, 2^16549081 is an apocalyptic number.

It is an amenable number.

16549081 is a deficient number, since it is larger than the sum of its proper divisors (1).

16549081 is an equidigital number, since it uses as much as digits as its factorization.

16549081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8640, while the sum is 34.

The square root of 16549081 is about 4068.0561697204. The cubic root of 16549081 is about 254.8343458257.

It can be divided in two parts, 16 and 549081, that multiplied together give a square (8785296 = 2964²).

The spelling of 16549081 in words is "sixteen million, five hundred forty-nine thousand, eighty-one".