81766380360 has 768 divisors, whose sum is σ = 314978388480. Its totient is φ = 16859136000.

The previous prime is 81766380349. The next prime is 81766380373. The reversal of 81766380360 is 6308366718.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 290983420 + ... + 290983700.

It is an arithmetic number, because the mean of its divisors is an integer number (410128110).

Almost surely, 2^81766380360 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 81766380360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (157489194240).

81766380360 is an abundant number, since it is smaller than the sum of its proper divisors (233212008120).

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

81766380360 is a wasteful number, since it uses less digits than its factorization.

81766380360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438 (or 427 counting only the distinct ones).

The product of its (nonzero) digits is 870912, while the sum is 48.

The spelling of 81766380360 in words is "eighty-one billion, seven hundred sixty-six million, three hundred eighty thousand, three hundred sixty".