81283263804 has 336 divisors, whose sum is σ = 236125774080. Its totient is φ = 24357231360.

The previous prime is 81283263749. The next prime is 81283263833. The reversal of 81283263804 is 40836238218.

81283263804 is a `hidden beast` number, since 8 + 1 + 2 + 8 + 3 + 2 + 638 + 0 + 4 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 81283263804.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 111 ways as a sum of consecutive naturals, for example, 289264144 + ... + 289264424.

It is an arithmetic number, because the mean of its divisors is an integer number (702755280).

Almost surely, 2^81283263804 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 81283263804, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (118062887040).

81283263804 is an abundant number, since it is smaller than the sum of its proper divisors (154842510276).

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

81283263804 is a wasteful number, since it uses less digits than its factorization.

81283263804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 572 (or 555 counting only the distinct ones).

The product of its (nonzero) digits is 442368, while the sum is 45.

The spelling of 81283263804 in words is "eighty-one billion, two hundred eighty-three million, two hundred sixty-three thousand, eight hundred four".