81852251307 has 4 divisors (see below), whose sum is σ = 109136335080. Its totient is φ = 54568167536.

The previous prime is 81852251303. The next prime is 81852251317. The reversal of 81852251307 is 70315225818.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81852251307 - 2² = 81852251303 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81852251303) 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, 13642041882 + ... + 13642041887.

It is an arithmetic number, because the mean of its divisors is an integer number (27284083770).

Almost surely, 2^81852251307 is an apocalyptic number.

81852251307 is a deficient number, since it is larger than the sum of its proper divisors (27284083773).

81852251307 is a wasteful number, since it uses less digits than its factorization.

81852251307 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27284083772.

The product of its (nonzero) digits is 134400, while the sum is 42.

The spelling of 81852251307 in words is "eighty-one billion, eight hundred fifty-two million, two hundred fifty-one thousand, three hundred seven".