81805394754 has 48 divisors (see below), whose sum is σ = 179753558400. Its totient is φ = 26883556128.

The previous prime is 81805394743. The next prime is 81805394821. The reversal of 81805394754 is 45749350818.

81805394754 is a `hidden beast` number, since 8 + 18 + 0 + 539 + 47 + 54 = 666.

It is a super-2 number, since 2×81805394754² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 81805394754.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 929112 + ... + 1013340.

It is an arithmetic number, because the mean of its divisors is an integer number (3744865800).

Almost surely, 2^81805394754 is an apocalyptic number.

81805394754 is an abundant number, since it is smaller than the sum of its proper divisors (97948163646).

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

81805394754 is a wasteful number, since it uses less digits than its factorization.

81805394754 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84999 (or 84996 counting only the distinct ones).

The product of its (nonzero) digits is 4838400, while the sum is 54.

The spelling of 81805394754 in words is "eighty-one billion, eight hundred five million, three hundred ninety-four thousand, seven hundred fifty-four".