666680072 has 16 divisors (see below), whose sum is σ = 1293129900. Its totient is φ = 321845440.

The previous prime is 666680071. The next prime is 666680081. The reversal of 666680072 is 270086666.

It can be written as a sum of positive squares in 2 ways, for example, as 645464836 + 21215236 = 25406^2 + 4606^2 .

It is not an unprimeable number, because it can be changed into a prime (666680071) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1436579 + ... + 1437042.

Almost surely, 2^666680072 is an apocalyptic number.

It is an amenable number.

666680072 is a deficient number, since it is larger than the sum of its proper divisors (626449828).

666680072 is a wasteful number, since it uses less digits than its factorization.

666680072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2873656 (or 2873652 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 41.

The square root of 666680072 is about 25820.1485665749. The cubic root of 666680072 is about 873.5863200157.

The spelling of 666680072 in words is "six hundred sixty-six million, six hundred eighty thousand, seventy-two".