21020011219 has 2 divisors, whose sum is σ = 21020011220. Its totient is φ = 21020011218.

The previous prime is 21020011141. The next prime is 21020011247. The reversal of 21020011219 is 91211002012.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21020011219 - 2⁷ = 21020011091 is a prime.

It is a super-2 number, since 2×21020011219² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21020011196 and 21020011205.

It is not a weakly prime, because it can be changed into another prime (21020011319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510005609 + 10510005610.

It is an arithmetic number, because the mean of its divisors is an integer number (10510005610).

Almost surely, 2^21020011219 is an apocalyptic number.

21020011219 is a deficient number, since it is larger than the sum of its proper divisors (1).

21020011219 is an equidigital number, since it uses as much as digits as its factorization.

21020011219 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 19.

The spelling of 21020011219 in words is "twenty-one billion, twenty million, eleven thousand, two hundred nineteen".