666225155720 has 32 divisors (see below), whose sum is σ = 1577901686400. Its totient is φ = 252464269248.

The previous prime is 666225155719. The next prime is 666225155789. The reversal of 666225155720 is 27551522666.

It is a super-2 number, since 2×666225155720² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

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, 438305264 + ... + 438306783.

It is an arithmetic number, because the mean of its divisors is an integer number (49309427700).

Almost surely, 2^666225155720 is an apocalyptic number.

It is an amenable number.

666225155720 is an abundant number, since it is smaller than the sum of its proper divisors (911676530680).

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

666225155720 is a wasteful number, since it uses less digits than its factorization.

666225155720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 876612077 (or 876612073 counting only the distinct ones).

The product of its (nonzero) digits is 1512000, while the sum is 47.

The spelling of 666225155720 in words is "six hundred sixty-six billion, two hundred twenty-five million, one hundred fifty-five thousand, seven hundred twenty".