81445856447703 has 16 divisors (see below), whose sum is σ = 118479520415232. Its totient is φ = 49355783400000.

The previous prime is 81445856447651. The next prime is 81445856447737. The reversal of 81445856447703 is 30774465854418.

It is a happy number.

It is not a de Polignac number, because 81445856447703 - 2⁶ = 81445856447639 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81445856947703) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 133233423 + ... + 133843328.

It is an arithmetic number, because the mean of its divisors is an integer number (7404970025952).

Almost surely, 2^{81445856447703} is an apocalyptic number.

81445856447703 is a deficient number, since it is larger than the sum of its proper divisors (37033663967529).

81445856447703 is a wasteful number, since it uses less digits than its factorization.

81445856447703 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 267086006.

The product of its (nonzero) digits is 361267200, while the sum is 66.

The spelling of 81445856447703 in words is "eighty-one trillion, four hundred forty-five billion, eight hundred fifty-six million, four hundred forty-seven thousand, seven hundred three".