21110019912869 has 2 divisors, whose sum is σ = 21110019912870. Its totient is φ = 21110019912868.

The previous prime is 21110019912833. The next prime is 21110019912889. The reversal of 21110019912869 is 96821991001112.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19338094200100 + 1771925712769 = 4397510^2 + 1331137^2 .

It is a cyclic number.

It is not a de Polignac number, because 21110019912869 - 2¹² = 21110019908773 is a prime.

It is a super-2 number, since 2×21110019912869² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21110019912889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555009956434 + 10555009956435.

It is an arithmetic number, because the mean of its divisors is an integer number (10555009956435).

Almost surely, 2^{21110019912869} is an apocalyptic number.

It is an amenable number.

21110019912869 is a deficient number, since it is larger than the sum of its proper divisors (1).

21110019912869 is an equidigital number, since it uses as much as digits as its factorization.

21110019912869 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 139968, while the sum is 50.

The spelling of 21110019912869 in words is "twenty-one trillion, one hundred ten billion, nineteen million, nine hundred twelve thousand, eight hundred sixty-nine".