666748220 has 24 divisors (see below), whose sum is σ = 1419895008. Its totient is φ = 262942400.

The previous prime is 666748183. The next prime is 666748223. The reversal of 666748220 is 22847666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666748223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 233351 + ... + 236190.

It is an arithmetic number, because the mean of its divisors is an integer number (59162292).

Almost surely, 2^666748220 is an apocalyptic number.

It is an amenable number.

666748220 is an abundant number, since it is smaller than the sum of its proper divisors (753146788).

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

666748220 is a wasteful number, since it uses less digits than its factorization.

666748220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 469621 (or 469619 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 41.

The square root of 666748220 is about 25821.4681999301. The cubic root of 666748220 is about 873.6160849833.

The spelling of 666748220 in words is "six hundred sixty-six million, seven hundred forty-eight thousand, two hundred twenty".