81127245699 has 12 divisors (see below), whose sum is σ = 121224620400. Its totient is φ = 52219836144.

The previous prime is 81127245677. The next prime is 81127245713. The reversal of 81127245699 is 99654272118.

It is a happy number.

81127245699 is a `hidden beast` number, since 8 + 1 + 1 + 2 + 72 + 4 + 569 + 9 = 666.

It is not a de Polignac number, because 81127245699 - 2⁷ = 81127245571 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81127244699) 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 11 ways as a sum of consecutive naturals, for example, 155415919 + ... + 155416440.

It is an arithmetic number, because the mean of its divisors is an integer number (10102051700).

Almost surely, 2^81127245699 is an apocalyptic number.

81127245699 is a deficient number, since it is larger than the sum of its proper divisors (40097374701).

81127245699 is a wasteful number, since it uses less digits than its factorization.

81127245699 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 310832394 (or 310832391 counting only the distinct ones).

The product of its digits is 2177280, while the sum is 54.

The spelling of 81127245699 in words is "eighty-one billion, one hundred twenty-seven million, two hundred forty-five thousand, six hundred ninety-nine".