21543093941 has 2 divisors, whose sum is σ = 21543093942. Its totient is φ = 21543093940.

The previous prime is 21543093917. The next prime is 21543093953. The reversal of 21543093941 is 14939034512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16015914916 + 5527179025 = 126554^2 + 74345^2 .

It is a cyclic number.

It is not a de Polignac number, because 21543093941 - 2⁶ = 21543093877 is a prime.

It is a super-2 number, since 2×21543093941² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21543093041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10771546970 + 10771546971.

It is an arithmetic number, because the mean of its divisors is an integer number (10771546971).

Almost surely, 2^21543093941 is an apocalyptic number.

It is an amenable number.

21543093941 is a deficient number, since it is larger than the sum of its proper divisors (1).

21543093941 is an equidigital number, since it uses as much as digits as its factorization.

21543093941 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 116640, while the sum is 41.

The spelling of 21543093941 in words is "twenty-one billion, five hundred forty-three million, ninety-three thousand, nine hundred forty-one".