989041661 has 2 divisors, whose sum is σ = 989041662. Its totient is φ = 989041660.

The previous prime is 989041649. The next prime is 989041663. The reversal of 989041661 is 166140989.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 511619161 + 477422500 = 22619^2 + 21850^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-989041661 is a prime.

Together with 989041663, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (989041663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 494520830 + 494520831.

It is an arithmetic number, because the mean of its divisors is an integer number (494520831).

Almost surely, 2^989041661 is an apocalyptic number.

It is an amenable number.

989041661 is a deficient number, since it is larger than the sum of its proper divisors (1).

989041661 is an equidigital number, since it uses as much as digits as its factorization.

989041661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 93312, while the sum is 44.

The square root of 989041661 is about 31449.0327514218. The cubic root of 989041661 is about 996.3337957053. Note that the first 3 decimals are identical.

The spelling of 989041661 in words is "nine hundred eighty-nine million, forty-one thousand, six hundred sixty-one".