166989649 has 2 divisors, whose sum is σ = 166989650. Its totient is φ = 166989648.

The previous prime is 166989631. The next prime is 166989659. The reversal of 166989649 is 946989661.

166989649 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 165585424 + 1404225 = 12868^2 + 1185^2 .

It is a cyclic number.

It is not a de Polignac number, because 166989649 - 2¹⁹ = 166465361 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 166989593 and 166989602.

It is not a weakly prime, because it can be changed into another prime (166989619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83494824 + 83494825.

It is an arithmetic number, because the mean of its divisors is an integer number (83494825).

Almost surely, 2^166989649 is an apocalyptic number.

It is an amenable number.

166989649 is a deficient number, since it is larger than the sum of its proper divisors (1).

166989649 is an equidigital number, since it uses as much as digits as its factorization.

166989649 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5038848, while the sum is 58.

The square root of 166989649 is about 12922.4474849001. The cubic root of 166989649 is about 550.6764668191.

The spelling of 166989649 in words is "one hundred sixty-six million, nine hundred eighty-nine thousand, six hundred forty-nine".