81247128802 has 64 divisors (see below), whose sum is σ = 145572053760. Its totient is φ = 33285758976.

The previous prime is 81247128793. The next prime is 81247128829. The reversal of 81247128802 is 20882174218.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 6978378 + ... + 6990010.

It is an arithmetic number, because the mean of its divisors is an integer number (2274563340).

Almost surely, 2^81247128802 is an apocalyptic number.

81247128802 is a deficient number, since it is larger than the sum of its proper divisors (64324924958).

81247128802 is a wasteful number, since it uses less digits than its factorization.

81247128802 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11915.

The product of its (nonzero) digits is 114688, while the sum is 43.

The spelling of 81247128802 in words is "eighty-one billion, two hundred forty-seven million, one hundred twenty-eight thousand, eight hundred two".