20003219981 has 2 divisors, whose sum is σ = 20003219982. Its totient is φ = 20003219980.

The previous prime is 20003219941. The next prime is 20003220001. The reversal of 20003219981 is 18991230002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19968516100 + 34703881 = 141310^2 + 5891^2 .

It is a cyclic number.

It is not a de Polignac number, because 20003219981 - 2⁶ = 20003219917 is a prime.

It is a super-2 number, since 2×20003219981² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20003219921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10001609990 + 10001609991.

It is an arithmetic number, because the mean of its divisors is an integer number (10001609991).

Almost surely, 2^20003219981 is an apocalyptic number.

It is an amenable number.

20003219981 is a deficient number, since it is larger than the sum of its proper divisors (1).

20003219981 is an equidigital number, since it uses as much as digits as its factorization.

20003219981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 35.

Adding to 20003219981 its reverse (18991230002), we get a palindrome (38994449983).

The spelling of 20003219981 in words is "twenty billion, three million, two hundred nineteen thousand, nine hundred eighty-one".