19804548457 has 2 divisors, whose sum is σ = 19804548458. Its totient is φ = 19804548456.

The previous prime is 19804548317. The next prime is 19804548481. The reversal of 19804548457 is 75484540891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17544591936 + 2259956521 = 132456^2 + 47539^2 .

It is a cyclic number.

It is not a de Polignac number, because 19804548457 - 2¹¹ = 19804546409 is a prime.

It is a super-2 number, since 2×19804548457² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 19804548398 and 19804548407.

It is not a weakly prime, because it can be changed into another prime (19804548557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9902274228 + 9902274229.

It is an arithmetic number, because the mean of its divisors is an integer number (9902274229).

Almost surely, 2^19804548457 is an apocalyptic number.

It is an amenable number.

19804548457 is a deficient number, since it is larger than the sum of its proper divisors (1).

19804548457 is an equidigital number, since it uses as much as digits as its factorization.

19804548457 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6451200, while the sum is 55.

The spelling of 19804548457 in words is "nineteen billion, eight hundred four million, five hundred forty-eight thousand, four hundred fifty-seven".