66643336 has 16 divisors (see below), whose sum is σ = 131533200. Its totient is φ = 31567824.

The previous prime is 66643333. The next prime is 66643337. The reversal of 66643336 is 63334666.

66643336 = T₆₆₆₄ + T₆₆₆₅ + T₆₆₆₆.

It is a junction number, because it is equal to n+sod(n) for n = 66643295 and 66643304.

It is not an unprimeable number, because it can be changed into a prime (66643333) 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, 219070 + ... + 219373.

It is an arithmetic number, because the mean of its divisors is an integer number (8220825).

Almost surely, 2^66643336 is an apocalyptic number.

66643336 is the 6666-th centered triangular number.

It is an amenable number.

66643336 is a deficient number, since it is larger than the sum of its proper divisors (64889864).

66643336 is a wasteful number, since it uses less digits than its factorization.

66643336 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438468 (or 438464 counting only the distinct ones).

The product of its digits is 139968, while the sum is 37.

The square root of 66643336 is about 8163.5369785406. The cubic root of 66643336 is about 405.4328269103.

It can be divided in two parts, 6664 and 3336, that added together give a 4-th power (10000 = 10⁴).

The spelling of 66643336 in words is "sixty-six million, six hundred forty-three thousand, three hundred thirty-six".