19899984827 has 2 divisors, whose sum is σ = 19899984828. Its totient is φ = 19899984826.

The previous prime is 19899984823. The next prime is 19899984857. The reversal of 19899984827 is 72848999891.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19899984827 - 2² = 19899984823 is a prime.

It is a super-2 number, since 2×19899984827² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (19899984821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9949992413 + 9949992414.

It is an arithmetic number, because the mean of its divisors is an integer number (9949992414).

Almost surely, 2^19899984827 is an apocalyptic number.

19899984827 is a deficient number, since it is larger than the sum of its proper divisors (1).

19899984827 is an equidigital number, since it uses as much as digits as its factorization.

19899984827 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 188116992, while the sum is 74.

The spelling of 19899984827 in words is "nineteen billion, eight hundred ninety-nine million, nine hundred eighty-four thousand, eight hundred twenty-seven".