19689161 has 2 divisors, whose sum is σ = 19689162. Its totient is φ = 19689160.

The previous prime is 19689151. The next prime is 19689167. The reversal of 19689161 is 16198691.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16605625 + 3083536 = 4075^2 + 1756^2 .

It is a cyclic number.

It is not a de Polignac number, because 19689161 - 2⁶ = 19689097 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (19689167) 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, 9844580 + 9844581.

It is an arithmetic number, because the mean of its divisors is an integer number (9844581).

Almost surely, 2^19689161 is an apocalyptic number.

It is an amenable number.

19689161 is a deficient number, since it is larger than the sum of its proper divisors (1).

19689161 is an equidigital number, since it uses as much as digits as its factorization.

19689161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 23328, while the sum is 41.

The square root of 19689161 is about 4437.2470068726. The cubic root of 19689161 is about 270.0281680717.

The spelling of 19689161 in words is "nineteen million, six hundred eighty-nine thousand, one hundred sixty-one".