666507309072 has 160 divisors (see below), whose sum is σ = 1970152187904. Its totient is φ = 192331814400.

The previous prime is 666507309037. The next prime is 666507309073. The reversal of 666507309072 is 270903705666.

It is not an unprimeable number, because it can be changed into a prime (666507309073) 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 31 ways as a sum of consecutive naturals, for example, 555247 + ... + 1281137.

Almost surely, 2^666507309072 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 666507309072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (985076093952).

666507309072 is an abundant number, since it is smaller than the sum of its proper divisors (1303644878832).

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

666507309072 is a wasteful number, since it uses less digits than its factorization.

666507309072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 725997 (or 725991 counting only the distinct ones).

The product of its (nonzero) digits is 2857680, while the sum is 51.

It can be divided in two parts, 666507 and 309072, that added together give a palindrome (975579).

The spelling of 666507309072 in words is "six hundred sixty-six billion, five hundred seven million, three hundred nine thousand, seventy-two".