866520725790720 has 5376 divisors, whose sum is σ = 3938894735376384. Its totient is φ = 158080381747200.

The previous prime is 866520725790697. The next prime is 866520725790821. The reversal of 866520725790720 is 27097527025668.

It is a tau number, because it is divible by the number of its divisors (5376).

It is a Harshad number since it is a multiple of its sum of digits (66).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 3061910691699 + ... + 3061910691981.

It is an arithmetic number, because the mean of its divisors is an integer number (732681312384).

Almost surely, 2^{866520725790720} is an apocalyptic number.

866520725790720 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 866520725790720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1969447367688192).

866520725790720 is an abundant number, since it is smaller than the sum of its proper divisors (3072374009585664).

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

866520725790720 is a wasteful number, since it uses less digits than its factorization.

866520725790720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 463 (or 428 counting only the distinct ones).

The product of its (nonzero) digits is 177811200, while the sum is 66.

The spelling of 866520725790720 in words is "eight hundred sixty-six trillion, five hundred twenty billion, seven hundred twenty-five million, seven hundred ninety thousand, seven hundred twenty".