19821328459 has 2 divisors, whose sum is σ = 19821328460. Its totient is φ = 19821328458.

The previous prime is 19821328433. The next prime is 19821328489. The reversal of 19821328459 is 95482312891.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19821328459 - 2⁵ = 19821328427 is a prime.

It is not a weakly prime, because it can be changed into another prime (19821328489) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9910664229 + 9910664230.

It is an arithmetic number, because the mean of its divisors is an integer number (9910664230).

Almost surely, 2^19821328459 is an apocalyptic number.

19821328459 is a deficient number, since it is larger than the sum of its proper divisors (1).

19821328459 is an equidigital number, since it uses as much as digits as its factorization.

19821328459 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1244160, while the sum is 52.

The spelling of 19821328459 in words is "nineteen billion, eight hundred twenty-one million, three hundred twenty-eight thousand, four hundred fifty-nine".