19841688541 has 2 divisors, whose sum is σ = 19841688542. Its totient is φ = 19841688540.

The previous prime is 19841688523. The next prime is 19841688571. The reversal of 19841688541 is 14588614891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16481167641 + 3360520900 = 128379^2 + 57970^2 .

It is a cyclic number.

It is not a de Polignac number, because 19841688541 - 2¹⁷ = 19841557469 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19841688511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9920844270 + 9920844271.

It is an arithmetic number, because the mean of its divisors is an integer number (9920844271).

Almost surely, 2^19841688541 is an apocalyptic number.

It is an amenable number.

19841688541 is a deficient number, since it is larger than the sum of its proper divisors (1).

19841688541 is an equidigital number, since it uses as much as digits as its factorization.

19841688541 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2211840, while the sum is 55.

The spelling of 19841688541 in words is "nineteen billion, eight hundred forty-one million, six hundred eighty-eight thousand, five hundred forty-one".