81240888686 has 32 divisors (see below), whose sum is σ = 124901805600. Its totient is φ = 39622556160.

The previous prime is 81240888683. The next prime is 81240888689. The reversal of 81240888686 is 68688804218.

It is an interprime number because it is at equal distance from previous prime (81240888683) and next prime (81240888689).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81240888683) 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, 4511681 + ... + 4529651.

It is an arithmetic number, because the mean of its divisors is an integer number (3903181425).

Almost surely, 2^81240888686 is an apocalyptic number.

81240888686 is a deficient number, since it is larger than the sum of its proper divisors (43660916914).

81240888686 is a wasteful number, since it uses less digits than its factorization.

81240888686 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18404.

The product of its (nonzero) digits is 9437184, while the sum is 59.

The spelling of 81240888686 in words is "eighty-one billion, two hundred forty million, eight hundred eighty-eight thousand, six hundred eighty-six".