16581941 has 2 divisors, whose sum is σ = 16581942. Its totient is φ = 16581940.

The previous prime is 16581937. The next prime is 16581973. The reversal of 16581941 is 14918561.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15437041 + 1144900 = 3929^2 + 1070^2 .

It is a cyclic number.

It is not a de Polignac number, because 16581941 - 2² = 16581937 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16581541) 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, 8290970 + 8290971.

It is an arithmetic number, because the mean of its divisors is an integer number (8290971).

Almost surely, 2^16581941 is an apocalyptic number.

It is an amenable number.

16581941 is a deficient number, since it is larger than the sum of its proper divisors (1).

16581941 is an equidigital number, since it uses as much as digits as its factorization.

16581941 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8640, while the sum is 35.

The square root of 16581941 is about 4072.0929508055. The cubic root of 16581941 is about 255.0029014151.

The spelling of 16581941 in words is "sixteen million, five hundred eighty-one thousand, nine hundred forty-one".