66643600 has 30 divisors (see below), whose sum is σ = 160112210. Its totient is φ = 26657280.

The previous prime is 66643597. The next prime is 66643601. The reversal of 66643600 is 634666.

It can be written as a sum of positive squares in 3 ways, for example, as 839056 + 65804544 = 916^2 + 8112^2 .

It is not an unprimeable number, because it can be changed into a prime (66643601) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 82905 + ... + 83704.

Almost surely, 2^66643600 is an apocalyptic number.

It is an amenable number.

66643600 is an abundant number, since it is smaller than the sum of its proper divisors (93468610).

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

66643600 is a wasteful number, since it uses less digits than its factorization.

66643600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166627 (or 166616 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 31.

The square root of 66643600 is about 8163.5531479865. The cubic root of 66643600 is about 405.4333622682.

The spelling of 66643600 in words is "sixty-six million, six hundred forty-three thousand, six hundred".