81609000103 has 2 divisors, whose sum is σ = 81609000104. Its totient is φ = 81609000102.

The previous prime is 81609000091. The next prime is 81609000139. The reversal of 81609000103 is 30100090618.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81609000103 - 2¹³ = 81608991911 is a prime.

It is a super-2 number, since 2×81609000103² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81609000703) 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, 40804500051 + 40804500052.

It is an arithmetic number, because the mean of its divisors is an integer number (40804500052).

Almost surely, 2^81609000103 is an apocalyptic number.

81609000103 is a deficient number, since it is larger than the sum of its proper divisors (1).

81609000103 is an equidigital number, since it uses as much as digits as its factorization.

81609000103 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 28.

The spelling of 81609000103 in words is "eighty-one billion, six hundred nine million, one hundred three", and thus it is an aban number.