21111233000021 has 2 divisors, whose sum is σ = 21111233000022. Its totient is φ = 21111233000020.

The previous prime is 21111233000003. The next prime is 21111233000069. The reversal of 21111233000021 is 12000033211112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21110992408900 + 240591121 = 4594670^2 + 15511^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21111233000021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21111233000521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555616500010 + 10555616500011.

It is an arithmetic number, because the mean of its divisors is an integer number (10555616500011).

Almost surely, 2^{21111233000021} is an apocalyptic number.

It is an amenable number.

21111233000021 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111233000021 is an equidigital number, since it uses as much as digits as its factorization.

21111233000021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 21111233000021 its reverse (12000033211112), we get a palindrome (33111266211133).

The spelling of 21111233000021 in words is "twenty-one trillion, one hundred eleven billion, two hundred thirty-three million, twenty-one", and thus it is an aban number.