21500111332643 has 2 divisors, whose sum is σ = 21500111332644. Its totient is φ = 21500111332642.

The previous prime is 21500111332541. The next prime is 21500111332669. The reversal of 21500111332643 is 34623311100512.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21500111332643 - 2⁸ = 21500111332387 is a prime.

It is not a weakly prime, because it can be changed into another prime (21500111332673) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10750055666321 + 10750055666322.

It is an arithmetic number, because the mean of its divisors is an integer number (10750055666322).

Almost surely, 2^{21500111332643} is an apocalyptic number.

21500111332643 is a deficient number, since it is larger than the sum of its proper divisors (1).

21500111332643 is an equidigital number, since it uses as much as digits as its factorization.

21500111332643 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12960, while the sum is 32.

The spelling of 21500111332643 in words is "twenty-one trillion, five hundred billion, one hundred eleven million, three hundred thirty-two thousand, six hundred forty-three".