81437846093 has 2 divisors, whose sum is σ = 81437846094. Its totient is φ = 81437846092.

The previous prime is 81437846059. The next prime is 81437846173. The reversal of 81437846093 is 39064873418.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 68163810724 + 13274035369 = 261082^2 + 115213^2 .

It is a cyclic number.

It is not a de Polignac number, because 81437846093 - 2⁶ = 81437846029 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81437846003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40718923046 + 40718923047.

It is an arithmetic number, because the mean of its divisors is an integer number (40718923047).

Almost surely, 2^81437846093 is an apocalyptic number.

It is an amenable number.

81437846093 is a deficient number, since it is larger than the sum of its proper divisors (1).

81437846093 is an equidigital number, since it uses as much as digits as its factorization.

81437846093 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3483648, while the sum is 53.

The spelling of 81437846093 in words is "eighty-one billion, four hundred thirty-seven million, eight hundred forty-six thousand, ninety-three".