81288196293 has 4 divisors (see below), whose sum is σ = 108384261728. Its totient is φ = 54192130860.

The previous prime is 81288196259. The next prime is 81288196331. The reversal of 81288196293 is 39269188218.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 81288196293 - 2¹² = 81288192197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81288196193) 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 in 3 ways as a sum of consecutive naturals, for example, 13548032713 + ... + 13548032718.

It is an arithmetic number, because the mean of its divisors is an integer number (27096065432).

Almost surely, 2^81288196293 is an apocalyptic number.

It is an amenable number.

81288196293 is a deficient number, since it is larger than the sum of its proper divisors (27096065435).

81288196293 is a wasteful number, since it uses less digits than its factorization.

81288196293 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27096065434.

The product of its digits is 2985984, while the sum is 57.

The spelling of 81288196293 in words is "eighty-one billion, two hundred eighty-eight million, one hundred ninety-six thousand, two hundred ninety-three".