21711019943 has 2 divisors, whose sum is σ = 21711019944. Its totient is φ = 21711019942.

The previous prime is 21711019933. The next prime is 21711019961. The reversal of 21711019943 is 34991011712.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21711019943 - 2⁶ = 21711019879 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21711019897 and 21711019906.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21711019933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10855509971 + 10855509972.

It is an arithmetic number, because the mean of its divisors is an integer number (10855509972).

Almost surely, 2^21711019943 is an apocalyptic number.

21711019943 is a deficient number, since it is larger than the sum of its proper divisors (1).

21711019943 is an equidigital number, since it uses as much as digits as its factorization.

21711019943 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13608, while the sum is 38.

The spelling of 21711019943 in words is "twenty-one billion, seven hundred eleven million, nineteen thousand, nine hundred forty-three".