81238627998 has 64 divisors (see below), whose sum is σ = 198782864640. Its totient is φ = 24387674400.

The previous prime is 81238627969. The next prime is 81238628039. The reversal of 81238627998 is 89972683218.

It is a congruent number.

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, 575533 + ... + 702648.

It is an arithmetic number, because the mean of its divisors is an integer number (3105982260).

Almost surely, 2^81238627998 is an apocalyptic number.

81238627998 is an abundant number, since it is smaller than the sum of its proper divisors (117544236642).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81238627998 is a wasteful number, since it uses less digits than its factorization.

81238627998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1278310 (or 1278304 counting only the distinct ones).

The product of its digits is 20901888, while the sum is 63.

The spelling of 81238627998 in words is "eighty-one billion, two hundred thirty-eight million, six hundred twenty-seven thousand, nine hundred ninety-eight".