666929912020 has 24 divisors (see below), whose sum is σ = 1434712641768. Its totient is φ = 260265331200.

The previous prime is 666929912003. The next prime is 666929912021. The reversal of 666929912020 is 20219929666.

It can be written as a sum of positive squares in 4 ways, for example, as 43332250896 + 623597661124 = 208164^2 + 789682^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666929912021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 406663761 + ... + 406665400.

It is an arithmetic number, because the mean of its divisors is an integer number (59779693407).

Almost surely, 2^666929912020 is an apocalyptic number.

It is an amenable number.

666929912020 is an abundant number, since it is smaller than the sum of its proper divisors (767782729748).

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

666929912020 is a wasteful number, since it uses less digits than its factorization.

666929912020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 813329211 (or 813329209 counting only the distinct ones).

The product of its (nonzero) digits is 1259712, while the sum is 52.

The spelling of 666929912020 in words is "six hundred sixty-six billion, nine hundred twenty-nine million, nine hundred twelve thousand, twenty".