21111199999999 has 2 divisors, whose sum is σ = 21111200000000. Its totient is φ = 21111199999998.

The previous prime is 21111199999913. The next prime is 21111200000071. The reversal of 21111199999999 is 99999999111112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21111199999999 - 2⁷ = 21111199999871 is a prime.

21111199999999 is a modest number, since divided by 9999999 gives 2111119 as remainder.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21111199999199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555599999999 + 10555600000000.

It is an arithmetic number, because the mean of its divisors is an integer number (10555600000000).

Almost surely, 2^{21111199999999} is an apocalyptic number.

21111199999999 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111199999999 is an equidigital number, since it uses as much as digits as its factorization.

21111199999999 is an evil number, because the sum of its binary digits is even.

The product of its digits is 86093442, while the sum is 79.

The spelling of 21111199999999 in words is "twenty-one trillion, one hundred eleven billion, one hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred ninety-nine".