18980073661 has 2 divisors, whose sum is σ = 18980073662. Its totient is φ = 18980073660.

The previous prime is 18980073643. The next prime is 18980073667. The reversal of 18980073661 is 16637008981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15858616761 + 3121456900 = 125931^2 + 55870^2 .

It is an emirp because it is prime and its reverse (16637008981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18980073661 - 2³¹ = 16832590013 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18980073667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9490036830 + 9490036831.

It is an arithmetic number, because the mean of its divisors is an integer number (9490036831).

Almost surely, 2^18980073661 is an apocalyptic number.

It is an amenable number.

18980073661 is a deficient number, since it is larger than the sum of its proper divisors (1).

18980073661 is an equidigital number, since it uses as much as digits as its factorization.

18980073661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 435456, while the sum is 49.

The spelling of 18980073661 in words is "eighteen billion, nine hundred eighty million, seventy-three thousand, six hundred sixty-one".