81316661303 has 2 divisors, whose sum is σ = 81316661304. Its totient is φ = 81316661302.

The previous prime is 81316661273. The next prime is 81316661381. The reversal of 81316661303 is 30316661318.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81316661303 - 2²⁰ = 81315612727 is a prime.

It is a super-2 number, since 2×81316661303² (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 (81316661383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40658330651 + 40658330652.

It is an arithmetic number, because the mean of its divisors is an integer number (40658330652).

Almost surely, 2^81316661303 is an apocalyptic number.

81316661303 is a deficient number, since it is larger than the sum of its proper divisors (1).

81316661303 is an equidigital number, since it uses as much as digits as its factorization.

81316661303 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 46656, while the sum is 38.

The spelling of 81316661303 in words is "eighty-one billion, three hundred sixteen million, six hundred sixty-one thousand, three hundred three".