81182721307 has 8 divisors (see below), whose sum is σ = 84294334800. Its totient is φ = 78091921824.

The previous prime is 81182721299. The next prime is 81182721379. The reversal of 81182721307 is 70312728118.

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

It is a cyclic number.

It is not a de Polignac number, because 81182721307 - 2³ = 81182721299 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81182721307.

It is not an unprimeable number, because it can be changed into a prime (81182721407) 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 7 ways as a sum of consecutive naturals, for example, 5195553 + ... + 5211154.

It is an arithmetic number, because the mean of its divisors is an integer number (10536791850).

Almost surely, 2^81182721307 is an apocalyptic number.

81182721307 is a deficient number, since it is larger than the sum of its proper divisors (3111613493).

81182721307 is a wasteful number, since it uses less digits than its factorization.

81182721307 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10407005.

The product of its (nonzero) digits is 37632, while the sum is 40.

The spelling of 81182721307 in words is "eighty-one billion, one hundred eighty-two million, seven hundred twenty-one thousand, three hundred seven".