81219144810 has 16 divisors (see below), whose sum is σ = 194925947616. Its totient is φ = 21658438608.

The previous prime is 81219144737. The next prime is 81219144863. The reversal of 81219144810 is 1844191218.

It is a super-2 number, since 2×81219144810² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1353652384 + ... + 1353652443.

It is an arithmetic number, because the mean of its divisors is an integer number (12182871726).

Almost surely, 2^81219144810 is an apocalyptic number.

81219144810 is an abundant number, since it is smaller than the sum of its proper divisors (113706802806).

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

81219144810 is a wasteful number, since it uses less digits than its factorization.

81219144810 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2707304837.

The product of its (nonzero) digits is 18432, while the sum is 39.

The spelling of 81219144810 in words is "eighty-one billion, two hundred nineteen million, one hundred forty-four thousand, eight hundred ten".