21150005111 has 2 divisors, whose sum is σ = 21150005112. Its totient is φ = 21150005110.

The previous prime is 21150005027. The next prime is 21150005113. The reversal of 21150005111 is 11150005112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21150005111 - 2³⁰ = 20076263287 is a prime.

It is a super-2 number, since 2×21150005111² (a number of 21 digits) contains 22 as substring.

Together with 21150005113, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21150005111.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21150005113) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10575002555 + 10575002556.

It is an arithmetic number, because the mean of its divisors is an integer number (10575002556).

Almost surely, 2^21150005111 is an apocalyptic number.

21150005111 is a deficient number, since it is larger than the sum of its proper divisors (1).

21150005111 is an equidigital number, since it uses as much as digits as its factorization.

21150005111 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 50, while the sum is 17.

Subtracting from 21150005111 its reverse (11150005112), we obtain a palindrome (9999999999).

The spelling of 21150005111 in words is "twenty-one billion, one hundred fifty million, five thousand, one hundred eleven".