666171670220 has 96 divisors (see below), whose sum is σ = 1616081725440. Its totient is φ = 225940780800.

The previous prime is 666171670201. The next prime is 666171670277. The reversal of 666171670220 is 22076171666.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10469261 + ... + 10532699.

It is an arithmetic number, because the mean of its divisors is an integer number (16834184640).

Almost surely, 2^666171670220 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 666171670220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (808040862720).

666171670220 is an abundant number, since it is smaller than the sum of its proper divisors (949910055220).

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

666171670220 is a wasteful number, since it uses less digits than its factorization.

666171670220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64263 (or 64261 counting only the distinct ones).

The product of its (nonzero) digits is 254016, while the sum is 44.

The spelling of 666171670220 in words is "six hundred sixty-six billion, one hundred seventy-one million, six hundred seventy thousand, two hundred twenty".