16661616149 has 2 divisors, whose sum is σ = 16661616150. Its totient is φ = 16661616148.

The previous prime is 16661616143. The next prime is 16661616161. The reversal of 16661616149 is 94161616661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13704214225 + 2957401924 = 117065^2 + 54382^2 .

It is a cyclic number.

It is not a de Polignac number, because 16661616149 - 2¹⁶ = 16661550613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16661616143) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8330808074 + 8330808075.

It is an arithmetic number, because the mean of its divisors is an integer number (8330808075).

Almost surely, 2^16661616149 is an apocalyptic number.

It is an amenable number.

16661616149 is a deficient number, since it is larger than the sum of its proper divisors (1).

16661616149 is an equidigital number, since it uses as much as digits as its factorization.

16661616149 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 279936, while the sum is 47.

The spelling of 16661616149 in words is "sixteen billion, six hundred sixty-one million, six hundred sixteen thousand, one hundred forty-nine".