19820093809 has 2 divisors, whose sum is σ = 19820093810. Its totient is φ = 19820093808.

The previous prime is 19820093791. The next prime is 19820093851. The reversal of 19820093809 is 90839002891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10440752400 + 9379341409 = 102180^2 + 96847^2 .

It is a cyclic number.

It is not a de Polignac number, because 19820093809 - 2¹¹ = 19820091761 is a prime.

It is a super-2 number, since 2×19820093809² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (19820093869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9910046904 + 9910046905.

It is an arithmetic number, because the mean of its divisors is an integer number (9910046905).

Almost surely, 2^19820093809 is an apocalyptic number.

It is an amenable number.

19820093809 is a deficient number, since it is larger than the sum of its proper divisors (1).

19820093809 is an equidigital number, since it uses as much as digits as its factorization.

19820093809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 279936, while the sum is 49.

The spelling of 19820093809 in words is "nineteen billion, eight hundred twenty million, ninety-three thousand, eight hundred nine".