81299699218 has 8 divisors (see below), whose sum is σ = 121950834048. Its totient is φ = 40649421204.

The previous prime is 81299699209. The next prime is 81299699219.

81299699218 is nontrivially palindromic in base 10.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 81299699218.

It is not an unprimeable number, because it can be changed into a prime (81299699219) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 140455 + ... + 426997.

It is an arithmetic number, because the mean of its divisors is an integer number (15243854256).

Almost surely, 2^81299699218 is an apocalyptic number.

81299699218 is a deficient number, since it is larger than the sum of its proper divisors (40651134830).

81299699218 is a wasteful number, since it uses less digits than its factorization.

81299699218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 428408.

The product of its digits is 10077696, while the sum is 64.

The spelling of 81299699218 in words is "eighty-one billion, two hundred ninety-nine million, six hundred ninety-nine thousand, two hundred eighteen".