21443514535081 has 2 divisors, whose sum is σ = 21443514535082. Its totient is φ = 21443514535080.

The previous prime is 21443514535067. The next prime is 21443514535103. The reversal of 21443514535081 is 18053541534412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17951321610000 + 3492192925081 = 4236900^2 + 1868741^2 .

It is a cyclic number.

It is not a de Polignac number, because 21443514535081 - 2²¹ = 21443512437929 is a prime.

It is a super-2 number, since 2×21443514535081² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21443514535981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10721757267540 + 10721757267541.

It is an arithmetic number, because the mean of its divisors is an integer number (10721757267541).

Almost surely, 2^{21443514535081} is an apocalyptic number.

It is an amenable number.

21443514535081 is a deficient number, since it is larger than the sum of its proper divisors (1).

21443514535081 is an equidigital number, since it uses as much as digits as its factorization.

21443514535081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1152000, while the sum is 46.

The spelling of 21443514535081 in words is "twenty-one trillion, four hundred forty-three billion, five hundred fourteen million, five hundred thirty-five thousand, eighty-one".