666071901824 has 128 divisors (see below), whose sum is σ = 1549548748800. Its totient is φ = 279245159424.

The previous prime is 666071901799. The next prime is 666071901827. The reversal of 666071901824 is 428109170666.

It is a tau number, because it is divible by the number of its divisors (128).

It is not an unprimeable number, because it can be changed into a prime (666071901827) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 160149857 + ... + 160154015.

It is an arithmetic number, because the mean of its divisors is an integer number (12105849600).

Almost surely, 2^666071901824 is an apocalyptic number.

666071901824 is a gapful number since it is divisible by the number (64) 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 666071901824, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (774774374400).

666071901824 is an abundant number, since it is smaller than the sum of its proper divisors (883476846976).

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

666071901824 is a wasteful number, since it uses less digits than its factorization.

666071901824 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8030 (or 8018 counting only the distinct ones).

The product of its (nonzero) digits is 870912, while the sum is 50.

The spelling of 666071901824 in words is "six hundred sixty-six billion, seventy-one million, nine hundred one thousand, eight hundred twenty-four".