21201110109943 has 2 divisors, whose sum is σ = 21201110109944. Its totient is φ = 21201110109942.

The previous prime is 21201110109931. The next prime is 21201110110007. The reversal of 21201110109943 is 34990101110212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21201110109943 - 2⁴¹ = 19002086854391 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21201110109899 and 21201110109908.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21201110109043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600555054971 + 10600555054972.

It is an arithmetic number, because the mean of its divisors is an integer number (10600555054972).

Almost surely, 2^{21201110109943} is an apocalyptic number.

21201110109943 is a deficient number, since it is larger than the sum of its proper divisors (1).

21201110109943 is an equidigital number, since it uses as much as digits as its factorization.

21201110109943 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3888, while the sum is 34.

The spelling of 21201110109943 in words is "twenty-one trillion, two hundred one billion, one hundred ten million, one hundred nine thousand, nine hundred forty-three".