666672400 has 45 divisors (see below), whose sum is σ = 1602922053. Its totient is φ = 266462400.

The previous prime is 666672337. The next prime is 666672407. The reversal of 666672400 is 4276666.

The square root of 666672400 is 25820.

It is a perfect power (a square), and thus also a powerful number.

666672400 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 240002064 + 426670336 = 15492^2 + 20656^2 .

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 666672400.

It is not an unprimeable number, because it can be changed into a prime (666672407) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 515755 + ... + 517045.

Almost surely, 2^666672400 is an apocalyptic number.

666672400 is the 25820-th square number.

It is an amenable number.

666672400 is an abundant number, since it is smaller than the sum of its proper divisors (936249653).

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

666672400 is an equidigital number, since it uses as much as digits as its factorization.

666672400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2600 (or 1298 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 37.

The cubic root of 666672400 is about 873.5829689931.

The spelling of 666672400 in words is "six hundred sixty-six million, six hundred seventy-two thousand, four hundred".