66665212 has 6 divisors (see below), whose sum is σ = 116664128. Its totient is φ = 33332604.

The previous prime is 66665197. The next prime is 66665213. The reversal of 66665212 is 21256666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66665213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8333148 + ... + 8333155.

Almost surely, 2^66665212 is an apocalyptic number.

It is an amenable number.

66665212 is a deficient number, since it is larger than the sum of its proper divisors (49998916).

66665212 is a wasteful number, since it uses less digits than its factorization.

66665212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16666307 (or 16666305 counting only the distinct ones).

The product of its digits is 25920, while the sum is 34.

The square root of 66665212 is about 8164.8767290143. The cubic root of 66665212 is about 405.4771838246.

The spelling of 66665212 in words is "sixty-six million, six hundred sixty-five thousand, two hundred twelve".