81016814800 has 30 divisors (see below), whose sum is σ = 194642898518. Its totient is φ = 32406725760.

The previous prime is 81016814789. The next prime is 81016814803. The reversal of 81016814800 is 841861018.

It can be written as a sum of positive squares in 3 ways, for example, as 6223316544 + 74793498256 = 78888^2 + 273484^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 81016814800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81016814803) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 101270619 + ... + 101271418.

Almost surely, 2^81016814800 is an apocalyptic number.

81016814800 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81016814800 is an abundant number, since it is smaller than the sum of its proper divisors (113626083718).

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

81016814800 is a wasteful number, since it uses less digits than its factorization.

81016814800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 202542055 (or 202542044 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 37.

The spelling of 81016814800 in words is "eighty-one billion, sixteen million, eight hundred fourteen thousand, eight hundred".