81372048808 has 8 divisors (see below), whose sum is σ = 152572591530. Its totient is φ = 40686024400.

The previous prime is 81372048743. The next prime is 81372048827. The reversal of 81372048808 is 80884027318.

It can be written as a sum of positive squares in only one way, i.e., 62111605284 + 19260443524 = 249222^2 + 138782^2 .

It is a tau number, because it is divible by the number of its divisors (8).

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 as a sum of consecutive naturals, namely, 5085753043 + ... + 5085753058.

Almost surely, 2^81372048808 is an apocalyptic number.

It is an amenable number.

81372048808 is a deficient number, since it is larger than the sum of its proper divisors (71200542722).

81372048808 is a wasteful number, since it uses less digits than its factorization.

81372048808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10171506107 (or 10171506103 counting only the distinct ones).

The product of its (nonzero) digits is 688128, while the sum is 49.

The spelling of 81372048808 in words is "eighty-one billion, three hundred seventy-two million, forty-eight thousand, eight hundred eight".