81893086319520 has 576 divisors, whose sum is σ = 330570061645824. Its totient is φ = 18066009415680.

The previous prime is 81893086319519. The next prime is 81893086319531. The reversal of 81893086319520 is 2591368039818.

81893086319520 is a `hidden beast` number, since 8 + 1 + 8 + 9 + 30 + 8 + 63 + 19 + 520 = 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 95 ways as a sum of consecutive naturals, for example, 116203734 + ... + 116906346.

It is an arithmetic number, because the mean of its divisors is an integer number (573906357024).

Almost surely, 2^{81893086319520} is an apocalyptic number.

81893086319520 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81893086319520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (165285030822912).

81893086319520 is an abundant number, since it is smaller than the sum of its proper divisors (248676975326304).

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

81893086319520 is a wasteful number, since it uses less digits than its factorization.

81893086319520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 703045 (or 703034 counting only the distinct ones).

The product of its (nonzero) digits is 22394880, while the sum is 63.

The spelling of 81893086319520 in words is "eighty-one trillion, eight hundred ninety-three billion, eighty-six million, three hundred nineteen thousand, five hundred twenty".