81854009687016 has 512 divisors, whose sum is σ = 272431077580800. Its totient is φ = 22264760770560.

The previous prime is 81854009686957. The next prime is 81854009687029. The reversal of 81854009687016 is 61078690045818.

81854009687016 is a `hidden beast` number, since 8 + 1 + 8 + 540 + 0 + 9 + 6 + 8 + 70 + 16 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 6837685911 + ... + 6837697881.

It is an arithmetic number, because the mean of its divisors is an integer number (532091948400).

Almost surely, 2^{81854009687016} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81854009687016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (136215538790400).

81854009687016 is an abundant number, since it is smaller than the sum of its proper divisors (190577067893784).

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

81854009687016 is a wasteful number, since it uses less digits than its factorization.

81854009687016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12926 (or 12916 counting only the distinct ones).

The product of its (nonzero) digits is 23224320, while the sum is 63.

The spelling of 81854009687016 in words is "eighty-one trillion, eight hundred fifty-four billion, nine million, six hundred eighty-seven thousand, sixteen".