21111121219 has 2 divisors, whose sum is σ = 21111121220. Its totient is φ = 21111121218.

The previous prime is 21111121211. The next prime is 21111121231. The reversal of 21111121219 is 91212111112.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21111121219 - 2³ = 21111121211 is a prime.

It is a super-2 number, since 2×21111121219² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21111121219.

It is not a weakly prime, because it can be changed into another prime (21111121211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555560609 + 10555560610.

It is an arithmetic number, because the mean of its divisors is an integer number (10555560610).

Almost surely, 2^21111121219 is an apocalyptic number.

21111121219 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111121219 is an equidigital number, since it uses as much as digits as its factorization.

21111121219 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 72, while the sum is 22.

The spelling of 21111121219 in words is "twenty-one billion, one hundred eleven million, one hundred twenty-one thousand, two hundred nineteen".