19726920049 has 2 divisors, whose sum is σ = 19726920050. Its totient is φ = 19726920048.

The previous prime is 19726920047. The next prime is 19726920089. The reversal of 19726920049 is 94002962791.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18318269025 + 1408651024 = 135345^2 + 37532^2 .

It is a cyclic number.

It is not a de Polignac number, because 19726920049 - 2¹ = 19726920047 is a prime.

Together with 19726920047, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 19726919984 and 19726920011.

It is not a weakly prime, because it can be changed into another prime (19726920047) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9863460024 + 9863460025.

It is an arithmetic number, because the mean of its divisors is an integer number (9863460025).

Almost surely, 2^19726920049 is an apocalyptic number.

It is an amenable number.

19726920049 is a deficient number, since it is larger than the sum of its proper divisors (1).

19726920049 is an equidigital number, since it uses as much as digits as its factorization.

19726920049 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 489888, while the sum is 49.

The spelling of 19726920049 in words is "nineteen billion, seven hundred twenty-six million, nine hundred twenty thousand, forty-nine".