20000019881 has 2 divisors, whose sum is σ = 20000019882. Its totient is φ = 20000019880.

The previous prime is 20000019791. The next prime is 20000019887. The reversal of 20000019881 is 18891000002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13862707600 + 6137312281 = 117740^2 + 78341^2 .

It is a cyclic number.

It is not a de Polignac number, because 20000019881 - 2²⁶ = 19932911017 is a prime.

It is a super-2 number, since 2×20000019881² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (20000019887) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10000009940 + 10000009941.

It is an arithmetic number, because the mean of its divisors is an integer number (10000009941).

Almost surely, 2^20000019881 is an apocalyptic number.

It is an amenable number.

20000019881 is a deficient number, since it is larger than the sum of its proper divisors (1).

20000019881 is an equidigital number, since it uses as much as digits as its factorization.

20000019881 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1152, while the sum is 29.

Adding to 20000019881 its reverse (18891000002), we get a palindrome (38891019883).

The spelling of 20000019881 in words is "twenty billion, nineteen thousand, eight hundred eighty-one".