19544420869 has 2 divisors, whose sum is σ = 19544420870. Its totient is φ = 19544420868.

The previous prime is 19544420839. The next prime is 19544420897. The reversal of 19544420869 is 96802444591.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18343451844 + 1200969025 = 135438^2 + 34655^2 .

It is a cyclic number.

It is not a de Polignac number, because 19544420869 - 2⁵ = 19544420837 is a prime.

It is a super-2 number, since 2×19544420869² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19544420809) 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, 9772210434 + 9772210435.

It is an arithmetic number, because the mean of its divisors is an integer number (9772210435).

Almost surely, 2^19544420869 is an apocalyptic number.

It is an amenable number.

19544420869 is a deficient number, since it is larger than the sum of its proper divisors (1).

19544420869 is an equidigital number, since it uses as much as digits as its factorization.

19544420869 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2488320, while the sum is 52.

The spelling of 19544420869 in words is "nineteen billion, five hundred forty-four million, four hundred twenty thousand, eight hundred sixty-nine".