19542111557 has 2 divisors, whose sum is σ = 19542111558. Its totient is φ = 19542111556.

The previous prime is 19542111551. The next prime is 19542111559. The reversal of 19542111557 is 75511124591.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18668849956 + 873261601 = 136634^2 + 29551^2 .

It is a cyclic number.

It is not a de Polignac number, because 19542111557 - 2²² = 19537917253 is a prime.

Together with 19542111559, 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 (19542111551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9771055778 + 9771055779.

It is an arithmetic number, because the mean of its divisors is an integer number (9771055779).

Almost surely, 2^19542111557 is an apocalyptic number.

It is an amenable number.

19542111557 is a deficient number, since it is larger than the sum of its proper divisors (1).

19542111557 is an equidigital number, since it uses as much as digits as its factorization.

19542111557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 63000, while the sum is 41.

The spelling of 19542111557 in words is "nineteen billion, five hundred forty-two million, one hundred eleven thousand, five hundred fifty-seven".