19361559221 has 2 divisors, whose sum is σ = 19361559222. Its totient is φ = 19361559220.

The previous prime is 19361559211. The next prime is 19361559223. The reversal of 19361559221 is 12295516391.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15893644900 + 3467914321 = 126070^2 + 58889^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19361559221 is a prime.

Together with 19361559223, 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 (19361559223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9680779610 + 9680779611.

It is an arithmetic number, because the mean of its divisors is an integer number (9680779611).

Almost surely, 2^19361559221 is an apocalyptic number.

It is an amenable number.

19361559221 is a deficient number, since it is larger than the sum of its proper divisors (1).

19361559221 is an equidigital number, since it uses as much as digits as its factorization.

19361559221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 145800, while the sum is 44.

The spelling of 19361559221 in words is "nineteen billion, three hundred sixty-one million, five hundred fifty-nine thousand, two hundred twenty-one".