20011001819 has 4 divisors (see below), whose sum is σ = 20551839744. Its totient is φ = 19470163896.

The previous prime is 20011001753. The next prime is 20011001827. The reversal of 20011001819 is 91810011002.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20011001819 is a prime.

It is a super-2 number, since 2×20011001819² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20011001794 and 20011001803.

It is not an unprimeable number, because it can be changed into a prime (20011001519) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 270418907 + ... + 270418980.

It is an arithmetic number, because the mean of its divisors is an integer number (5137959936).

Almost surely, 2^20011001819 is an apocalyptic number.

20011001819 is a deficient number, since it is larger than the sum of its proper divisors (540837925).

20011001819 is an equidigital number, since it uses as much as digits as its factorization.

20011001819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 540837924.

The product of its (nonzero) digits is 144, while the sum is 23.

The spelling of 20011001819 in words is "twenty billion, eleven million, one thousand, eight hundred nineteen".