66641216 has 14 divisors (see below), whose sum is σ = 132241290. Its totient is φ = 33320576.

The previous prime is 66641209. The next prime is 66641221. The reversal of 66641216 is 61214666.

It can be written as a sum of positive squares in only one way, i.e., 34105600 + 32535616 = 5840^2 + 5704^2 .

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 520571 + ... + 520698.

Almost surely, 2^66641216 is an apocalyptic number.

It is an amenable number.

66641216 is a deficient number, since it is larger than the sum of its proper divisors (65600074).

66641216 is a wasteful number, since it uses less digits than its factorization.

66641216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1041281 (or 1041271 counting only the distinct ones).

The product of its digits is 10368, while the sum is 32.

The square root of 66641216 is about 8163.4071318292. The cubic root of 66641216 is about 405.4285277722.

The spelling of 66641216 in words is "sixty-six million, six hundred forty-one thousand, two hundred sixteen".